Soma-notes - User contributions [en]

Talk:COMP 3000 Essay 2 2010 Question 11

2010-12-02T22:21:16Z

ScottG:

--[[User:ScottG|ScottG]] 22:21, 2 December 2010 (UTC) As I mentioned, the info came from, mostly, 'Timekeeping in Virtual Machines' (2nd point in the References section). Also, technically speaking direct citations are only ever required when taking quotes from something or using specific numbers, and since I didn't use either, didn't see the point in citing. Which seems lazy, but I've never lost any marks for a lack of citing on essays before, so figure it's probably not a big deal.

The guest time-keeping section is really good but requires citations. Does someone know where exactly the info came from? - Fedor

Hi, I'm making some cosmetic changes to style, grammar&citation-format. - Fedor

--[[User:Spanke|Spanke]] 00:19, 2 December 2010 (UTC) Finished Timers, I hate 3004...

--[[User:Jjpwilso|Jjpwilso]] 00:03, 2 December 2010 (UTC) I'll check for some more references on the ACM and IEEE databases. In the meantime I thought I'd mention what Anil said regarding critique. He suggested we should consider other approaches to the same solution, such as modifying NTP with a different heuristic. I'll see what I can dig up in other papers on NTP.

--[[User:ScottG|ScottG]] 22:06, 1 December 2010 (UTC) I'm assuming you meant for me to add my references, yes? I really only used the article, and 'Timekeeping in Virtual Machines' which I went to add, but is already on there. I've looked for other articles to try to get how others have looked at it that aren't VMware, but there really isn't a huge amount out there dealing ''specifically'' with guest timekeeping (unless I've gone Google-blind, which has admittedly happened before). Mostly I ran into links pointing to that specific article.

--[[User:Sblais2|Sblais2]] 17:50, 1 December 2010 (UTC) I added stuf into the Research problems. I think I summarized most of them. If I forgot any, please add them in. I also added the missing references in the reference section. For Fedor, we seem to miss some content in 2 sections. Also, you could read through the other section and add/change some pertinent information that might've been missed that would make this essay even better.

--[[User:Sblais2|Sblais2]] 15:11, 1 December 2010 (UTC) Would it be possible to add your references at the bottom please? Even if it is a link. I have added the article link at the top of the essay.

Hey guys, sorry its taken me a while to post here. If there is a particular topic that needs researching, I could spend some hours doing that tomorrow - suggestions? Also, I intend to fix up the style&structure after everything is done as I am quite good with that.

Fedor

--[[User:ScottG|ScottG]] 21:36, 26 November 2010 (UTC) So I was a little (more than a little) behind on my initially estimated time for getting stuff up on Guest Timekeeping, but that's the gist of it there now. I'm going to try to buff it up a bit before it's due, since what I put in is a bit rougher than I'd like. If I seem to be missing something that should be pretty obvious, let me know and I'll work it in.

--[[User:Jjpwilso|Jjpwilso]] 15:49, 23 November 2010 (UTC) I've been completely swamped with COMP3004 stuff (among other things) and feeling guilty as hell about this essay. The good news, for those who might have missed today's lecture, is we have an extension of one week. Phew!!

--[[User:Sblais2|Sblais2]] 21:29, 22 November 2010 (UTC) I have added a small part to the background section. I have created by hand a diagram explaining how it works. I tried to find an original way of doing it but it is the same diagram everywhere. Please feel free to comment here or by sending me an email.

--[[User:AbsMechanik|AbsMechanik]] 19:46, 22 November 2010 (UTC) Here's what my research has led me to so far. I'm trying to come up with good points for the research problem, contribution and critique part of this essay. Here's a bunch of links, I've come across. I think there will be a few more tonight. Feel free to read through 'em:
 http://www.vmware.com/files/pdf/Timekeeping-In-VirtualMachines.pdf
 http://www.xen.org/files/xen_interface.pdf
 http://www.microsoft.com/whdc/system/sysinternals/mm-timer.mspx
 http://www.intel.com/hardwaredesign/hpetspec_1.pdf
 http://www.cubinlab.ee.unimelb.edu.au/radclock/

--[[User:ScottG|ScottG]] 18:55, 22 November 2010 (UTC) I'm good taking the Guest Timekeeping section. Hopefully I'll have some stuff up tonight or early tomorrow for it.

--[[User:Sblais2|Sblais2]] 17:14, 22 November 2010 (UTC) I will be working on the Background section. I will dedicate it to explain some of the key concepts that are used in the research paper that will allow the readers to have a better understanding on the rest of our essay. The structure you've put in place looks good but it might get modified, depending on the text will flow. The diagram is a good idea. I will drawn a simple one and add it in. Feel free again to critique.

--[[User:Jjpwilso|Jjpwilso]] 15:12, 16 November 2010 (UTC) I wanted to get a structure started, so I have stubbed out the first section. Note: some of the sub-sections might belong in the Research Problem section but we can easily move them if they fit there. Let's use this area to plan who is doing what. Feel free to critique any of my submissions. When you comment here, please put your comments at the very top so we can easily see recent posts.

=Participants=
(X) Blais Sylvain sblais2 - Email: syl20blais@gmail.com 
(X) Graham Scott sgraham6 
(X) Ilitchev Fedor filitche fedor dot ilitchev at gmail dot com 
(X) Panke Shane spanke 
(X) Shukla Abhinav ashukla2 
(X) Wilson Robert jjpwilso

Talk:COMP 3000 Essay 2 2010 Question 11

2010-12-01T22:06:02Z

ScottG:

--[[User:ScottG|ScottG]] 22:06, 1 December 2010 (UTC) I'm assuming you meant for me to add my references, yes? I really only used the article, and 'Timekeeping in Virtual Machines' which I went to add, but is already on there. I've looked for other articles to try to get how others have looked at it that aren't VMware, but there really isn't a huge amount out there dealing ''specifically'' with guest timekeeping (unless I've gone Google-blind, which has admittedly happened before). Mostly I ran into links pointing to that specific article.

--[[User:Sblais2|Sblais2]] 17:50, 1 December 2010 (UTC) I added stuf into the Research problems. I think I summarized most of them. If I forgot any, please add them in. I also added the missing references in the reference section. For Fedor, we seem to miss some content in 2 sections. Also, you could read through the other section and add/change some pertinent information that might've been missed that would make this essay even better.

--[[User:Sblais2|Sblais2]] 15:11, 1 December 2010 (UTC) Would it be possible to add your references at the bottom please? Even if it is a link. I have added the article link at the top of the essay.

Hey guys, sorry its taken me a while to post here. If there is a particular topic that needs researching, I could spend some hours doing that tomorrow - suggestions? Also, I intend to fix up the style&structure after everything is done as I am quite good with that.

Fedor

--[[User:ScottG|ScottG]] 21:36, 26 November 2010 (UTC) So I was a little (more than a little) behind on my initially estimated time for getting stuff up on Guest Timekeeping, but that's the gist of it there now. I'm going to try to buff it up a bit before it's due, since what I put in is a bit rougher than I'd like. If I seem to be missing something that should be pretty obvious, let me know and I'll work it in.

--[[User:Jjpwilso|Jjpwilso]] 15:49, 23 November 2010 (UTC) I've been completely swamped with COMP3004 stuff (among other things) and feeling guilty as hell about this essay. The good news, for those who might have missed today's lecture, is we have an extension of one week. Phew!!

--[[User:Sblais2|Sblais2]] 21:29, 22 November 2010 (UTC) I have added a small part to the background section. I have created by hand a diagram explaining how it works. I tried to find an original way of doing it but it is the same diagram everywhere. Please feel free to comment here or by sending me an email.

--[[User:AbsMechanik|AbsMechanik]] 19:46, 22 November 2010 (UTC) Here's what my research has led me to so far. I'm trying to come up with good points for the research problem, contribution and critique part of this essay. Here's a bunch of links, I've come across. I think there will be a few more tonight. Feel free to read through 'em:
 http://www.vmware.com/files/pdf/Timekeeping-In-VirtualMachines.pdf
 http://www.xen.org/files/xen_interface.pdf
 http://www.microsoft.com/whdc/system/sysinternals/mm-timer.mspx
 http://www.intel.com/hardwaredesign/hpetspec_1.pdf
 http://www.cubinlab.ee.unimelb.edu.au/radclock/

--[[User:ScottG|ScottG]] 18:55, 22 November 2010 (UTC) I'm good taking the Guest Timekeeping section. Hopefully I'll have some stuff up tonight or early tomorrow for it.

--[[User:Sblais2|Sblais2]] 17:14, 22 November 2010 (UTC) I will be working on the Background section. I will dedicate it to explain some of the key concepts that are used in the research paper that will allow the readers to have a better understanding on the rest of our essay. The structure you've put in place looks good but it might get modified, depending on the text will flow. The diagram is a good idea. I will drawn a simple one and add it in. Feel free again to critique.

--[[User:Jjpwilso|Jjpwilso]] 15:12, 16 November 2010 (UTC) I wanted to get a structure started, so I have stubbed out the first section. Note: some of the sub-sections might belong in the Research Problem section but we can easily move them if they fit there. Let's use this area to plan who is doing what. Feel free to critique any of my submissions. When you comment here, please put your comments at the very top so we can easily see recent posts.

=Participants=
(X) Blais Sylvain sblais2 - Email: syl20blais@gmail.com 
(X) Graham Scott sgraham6 
(X) Ilitchev Fedor filitche fedor dot ilitchev at gmail dot com 
(X) Panke Shane spanke 
(X) Shukla Abhinav ashukla2 
(X) Wilson Robert jjpwilso

Talk:COMP 3000 Essay 2 2010 Question 11

2010-11-26T21:36:24Z

ScottG:

--[[User:ScottG|ScottG]] 21:36, 26 November 2010 (UTC) So I was a little (more than a little) behind on my initially estimated time for getting stuff up on Guest Timekeeping, but that's the gist of it there now. I'm going to try to buff it up a bit before it's due, since what I put in is a bit rougher than I'd like. If I seem to be missing something that should be pretty obvious, let me know and I'll work it in.

--[[User:Jjpwilso|Jjpwilso]] 15:49, 23 November 2010 (UTC) I've been completely swamped with COMP3004 stuff (among other things) and feeling guilty as hell about this essay. The good news, for those who might have missed today's lecture, is we have an extension of one week. Phew!!

--[[User:Sblais2|Sblais2]] 21:29, 22 November 2010 (UTC) I have added a small part to the background section. I have created by hand a diagram explaining how it works. I tried to find an original way of doing it but it is the same diagram everywhere. Please feel free to comment here or by sending me an email.

--[[User:AbsMechanik|AbsMechanik]] 19:46, 22 November 2010 (UTC) Here's what my research has led me to so far. I'm trying to come up with good points for the research problem, contribution and critique part of this essay. Here's a bunch of links, I've come across. I think there will be a few more tonight. Feel free to read through 'em:
 http://www.vmware.com/files/pdf/Timekeeping-In-VirtualMachines.pdf
 http://www.xen.org/files/xen_interface.pdf
 http://www.microsoft.com/whdc/system/sysinternals/mm-timer.mspx
 http://www.intel.com/hardwaredesign/hpetspec_1.pdf
 http://www.cubinlab.ee.unimelb.edu.au/radclock/

--[[User:ScottG|ScottG]] 18:55, 22 November 2010 (UTC) I'm good taking the Guest Timekeeping section. Hopefully I'll have some stuff up tonight or early tomorrow for it.

--[[User:Sblais2|Sblais2]] 17:14, 22 November 2010 (UTC) I will be working on the Background section. I will dedicate it to explain some of the key concepts that are used in the research paper that will allow the readers to have a better understanding on the rest of our essay. The structure you've put in place looks good but it might get modified, depending on the text will flow. The diagram is a good idea. I will drawn a simple one and add it in. Feel free again to critique.

--[[User:Jjpwilso|Jjpwilso]] 15:12, 16 November 2010 (UTC) I wanted to get a structure started, so I have stubbed out the first section. Note: some of the sub-sections might belong in the Research Problem section but we can easily move them if they fit there. Let's use this area to plan who is doing what. Feel free to critique any of my submissions. When you comment here, please put your comments at the very top so we can easily see recent posts.

=Participants=
(X) Blais Sylvain sblais2 - Email: syl20blais@gmail.com 
(X) Graham Scott sgraham6 
(X) Ilitchev Fedor filitche fedor dot ilitchev at gmail dot com 
(X) Panke Shane spanke 
(X) Shukla Abhinav ashukla2 
(X) Wilson Robert jjpwilso

COMP 3000 Essay 2 2010 Question 11

2010-11-26T21:33:49Z

ScottG:

=Background Concepts=

To better understand this paper, it is very important to have a good understanding of the general concepts breached in it. For example, we all know what clocks are in our day-to-day life but what are they in the context of computing? In this section, we will describe concepts like timekeeping, hardware/software clocks, the advantages and disadvantages of the different available counters, synchronization algorithms and explains what is a para-virtualized system.

===Timekeeping===

Since thousands of years, men have tried to find better ways to keep track of time. From sundials to atomic clocks, they were all made for the specific purpose of measuring the passage of time. This is not so different in computer operating systems. It is typically done in one of two ways: tick counting and tickless timekeeping[1]. Tick counting is when the operating system sets up an hardware device, generally a CPU, to interrupt at a certain rate. So each time one of those interrupts are called(a tick), the operating system will keep track of it in a counter. That will tell the system how much time has passed. In tickless timekeeping, instead of the OS keeping track of time through interrupts, a hardware device is used instead starting its own counter when the system is booted. The OS just need to read the counter from it when needed. Tickless timekeeping seems to be the better way to keep track of time because it doesn’t hog the CPU with hardware interrupts however, its performance is very dependent on the type of hardware used. Another disadvantages is that they tend to drift and can cause inaccuracy. I will explains those drifts later. But both of these are just counters. They don’t know what is the actual real-time. To remedy that, either a computer gets its time from a battery-backed real-time clock or it queries a network time server(NTP) to get the current time. The computer can also use software in the form of a daemon that will run periodically to make adjustments to the time.

===Clocks===

Computer “clocks” or “timers” can be hardware based, software based or they can even be an hybrid. The most commonly found timer is the hardware timer. All of the hardware timers can be generally described by this diagram where some have either more or less features:

Diagram1. Timer Abstraction

[[File:Timerabstract.jpg]]

This diagram nicely represent how tick counting works[2]. The oscillator runs at a predetermine frequency. The operating system might have to mesure it when the system boots. The counter starts with a predetermined value which can be set by software. For every cycle of the oscillator, the counter counts down one unit. When it reaches zero, its generates an output signal that might interrupt the CPU. That same interrupt will then allow the counter’s initial value to be reloaded into the counter and the process begins again. As I said earlier, not all hardware timer works exactly like that. Some actually counts up, doesn't use interrupts or doesn't have an initial counter value but they still follow the same principle.

===Timers===
# PIT is useful for generating interrupts at regular intervals through its three channels. Channel 0 is bound to IRQ0 which interrupts the CPU at regular intervals. Channel 1 is specific to each system and Channel 2 is connected to the speaker system. As such, we only need to concern ourselves with Channel 0. [http://www.osdever.net/bkerndev/Docs/pit.htm]
# CMOS RTC (I will fill these in later) --[[User:Spanke|Spanke]]
# Local APIC
# ACPI
# TSC
# HPET

==Guest Timekeeping==

Guest timekeeping is done using the same general methods as any computer timekeeping, using either tick counting or tickless systems. Where the two begin to differ, however, is that a host operating system is able to communicate directly with the physical hardware, while the guest operating system is unable to do so, having to communicate with the host system that it wants to communicate with the hardware. Having to do this is the greatest source of the guest operating system's clock losing accuracy, or more simply called drifting.

===Sources of Drift===

When a guest operating system is started, its clock simply synchronizes with the host's – some virtual machines such as VMware also do this when it is resumed from a suspended state, or restored from a snapshot – so it is easy to think that, since it starts off correctly the guest's clock will continue to be correct. That is, of course, incorrect. The first source of drift is simply due to the drift a host incurs in its own timekeeping. A clock is almost never entirely accurate, having a slight error due to the time used to communicate with the counter, even on the host system, and because the guest communicates with the host in order to keep track of its time, an error in the host's time is not only passed on to the guest, but because the host is trying to correct its own time the guest's request for a count is given slightly less priority, making it yet again lose accuracy. The larger the drift in the host, the larger the drift in the guest, as the host's drift simply compounds the issue.

Aside from the host's own drift, the other cause of drift in the virtual environment is the fact that the it is treated like a process by the host. In and of itself this doesn't seem like a problem, but because of it it can be denied the CPU time required, or allocated less memory than needed. With restricted CPU time, it's easy for the requested ticks or requested read of a counter to pile up and create a backlog of requests, or simply receive the requested data late enough to throw its clock off. With memory, if the virtual environment does not have enough allocated to it by the host it can run into the problem of swapping out pages that are needed soon. Swapping the pages back in will momentarily bring the entire virtual environment to a halt, so ticks are missed and the clock falls behind.

===Impact of Drift===

The impact of drift essentially boils down to round-off errors and lost ticks. The practical impact of drift, however, is quite apparent in any automated system. For a relatable real-world example, though not in a virtual environment, in a factory's assembly line, the machinery is finely tuned to do its own specific part at certain intervals, and it generally does so with impressive efficiency. If the clock in the system were to drift, however, a specific machine may move too soon or too late, bringing the line to a potentially catastrophic halt. In a virtual environment, drift is a bit more subtle, as one result of it could be skewed process scheduling – some schedulers give a certain amount of time to a process before moving on, but if the guest's time has drifted substantially, when it tries to correct its time it could give more or less time to the processes in the scheduler.

===Compensation Strategies===

There are a number of compensation strategies for dealing with drift, depending on the cause of it. If the problem is due to CPU management issues, then the host can give more CPU time to the virtual machine, or it can lower the timer interrupt rate – or simply use a tickless counter. If it is due to a memory management issue, allocating more memory to the virtual environment should prevent the system from needing to swap out page files so often.

If the issue is from neither of those, but simply due to the inevitable lag when the guest communicates with the hardware via the host, then there are other methods to correct the drift. Most systems natively have algorithms built in to correct the time if it gets too far ahead or behind real time, though they are not without their own faults; if the time is set ahead when catching up, the backlog of ticks it has built up may not be cleared, so it could potentially set itself ahead multiple times until the backlog is dealt with. Tools built into the virtual machine itself can also deal with drift to an extent, as VMware Tools does. This kind of tool checks to see if the clock's error is within a certain margin. If it exceeds the margin, then the backlog is set to zero – to prevent the issue mentioned with the native algorithms – and resynchronizes with the host clock before the guest goes back to keeping track of time as it normally would.

=Research problem=
=Contribution=
=Critique=
=References=

1. Timekeeping in Virtual Machines, Information Guide from VMWare. http://www.vmware.com/files/pdf/Timekeeping-In-VirtualMachines.pdf

2. Modern Operating System 3rd Edition, by Andrew S. Tanenbaum, published by Pearson.

Talk:COMP 3000 Essay 2 2010 Question 11

2010-11-22T18:55:44Z

ScottG:

--[[User:ScottG|ScottG]] 18:55, 22 November 2010 (UTC) I'm good taking the Guest Timekeeping section. Hopefully I'll have some stuff up tonight or early tomorrow for it.

--[[User:Sblais2|Sblais2]] 17:14, 22 November 2010 (UTC) I will be working on the Background section. I will dedicate it to explain some of the key concepts that are used in the research paper that will allow the readers to have a better understanding on the rest of our essay. The structure you've put in place looks good but it might get modified, depending on the text will flow. The diagram is a good idea. I will drawn a simple one and add it in. Feel free again to critique.

--[[User:Jjpwilso|Jjpwilso]] 15:12, 16 November 2010 (UTC) I wanted to get a structure started, so I have stubbed out the first section. Note: some of the sub-sections might belong in the Research Problem section but we can easily move them if they fit there. Let's use this area to plan who is doing what. Feel free to critique any of my submissions. When you comment here, please put your comments at the very top so we can easily see recent posts.

=Participants=
(X) Blais Sylvain sblais2 - Email: syl20blais@gmail.com 
(X) Graham Scott sgraham6 
(X) Ilitchev Fedor filitche fedor dot ilitchev at gmail dot com 
(X) Panke Shane spanke 
(X) Shukla Abhinav ashukla2 
(X) Wilson Robert jjpwilso

Talk:COMP 3000 Essay 2 2010 Question 11

2010-11-11T18:41:12Z

ScottG:

Please mark an X if you are able to participate.

( ) Blais Sylvain sblais2 
(X) Graham Scott sgraham6 
( ) Ilitchev Fedor filitche 
( ) Panke Shane spanke 
( ) Shukla Abhinav ashukla2 
(X) Wilson Robert jjpwilso

Talk:COMP 3000 Essay 1 2010 Question 4

2010-10-13T22:37:25Z

ScottG: /* Discussion */

== Discussion ==

9 am Friday, since it's due Thursday night. As for the papers, I seem to recall him saying that we should be using published papers, but if it's non-published and by someone who's clearly an expert (instead of some random blogger or something) that it'd be okay. If you're not sure, though, give him a shout; he's pretty quick at responding.

--[[User:ScottG|ScottG]] 22:37, 13 October 2010 (UTC)

Guys, are we allowed to use unpublished papers? there is this paper in the SPIN website that is really helpful. I'm not sure if I'm allowed to use it for our essay, anybody has an idea?

Anil said something about grading the essays around 9 AM (or was it PM?). Was he talking about thursday or friday?

--[[User:Ymoussou|Youcef M.]] 21:57, 13 October 2010 (UTC)

Okay, I've basically got the Lisp section done. Gonna probably go back and tweak it, but at least it's there. And I added in what I used as references in the References section as per MLA style.

I can take a look at writing up something for the C/C++ part as well, just not sure how much I'll be able to get in the time I've got to spare between other courses right now. But I'll certainly try.

--[[User:ScottG|ScottG]] 15:37, 13 October 2010 (UTC)

Could somebody add a bit in the introduction on what it means to be an operating system written in C/C++? One focus should probably be the notion of process as hinted by Anil. There are probably other distinctions that can be dredged up too.

--[[User:Jjpwilso|Jjpwilso]] 02:57, 13 October 2010 (UTC)

Got some stuff up, rough copy only. Meant to get more done, but family stuff came up. More to come tomorrow.

--[[User:ScottG|ScottG]] 02:26, 13 October 2010 (UTC)

Right then, I'm on it.

--[[User:Mkugler|Mkugler]] 01:19, 13 October 2010 (UTC)

Hi MK, and welcome to the group. Anil mentioned Oberon just today, which is apparently another OS based on a cousin of modula-3. If you could find a way to extend the Modula-3 section with Oberon, perhaps with your own subsection (Youcef has already started with a SPIN section) that should help us round things up nicely. Note the goal is to compare capabilities with C/C++, so feel free to take a global view for thematic consistency too. I'll be doing a bit more in this respect on the Smalltalk section. As Anil said in lecture today, it should hold together as an essay even without the wiki-ish headings.

--[[User:Jjpwilso|Jjpwilso]] 01:07, 13 October 2010 (UTC)

Hey guys. I'm a bit late to the punch on this as I've been preoccupied with a ton of other stuff. I've read through what you've all done thus far and frankly think it's phenomenal, which brings me to my quandry. I wasn't here when you all laid claim to the various components of the essay and am not entirely certain where my efforts should be directed. I noticed that LISP so far is empty, but that it was claimed by ScottG on the 8th.

Is there anywhere in particular where you would like me to work? I'm committed to spending the better part of the next 48 hours entirely on this, so I can put together anything remaining that's needed. If you guys can't get back to me, I'll just expand on whatever I can find more information on.

--[[User:Mkugler|Mkugler]] 23:16, 12 October 2010 (UTC)

The SPIN work is looking good Youcef. Note: please try to put links to your sources in the text so we can see where your ideas are coming from.

--[[User:Jjpwilso|Jjpwilso]] 20:45, 12 October 2010 (UTC)

Anil gave me another clue into how he was thinking of comparisons between these OSes and C/C++. For Smalltalk at least the central theme mentions nothing about processes. Smalltalk is about objects, methods, and messages rather than the traditional C notion of processes manipulating data. This distinction or something similar to it may be useful when looking at other operating systems we're exploring.

--[[User:Jjpwilso|Jjpwilso]] 20:42, 12 October 2010 (UTC)

I've got some small amount of comparison in mine (haven't posted it, since I'm still trying to compile info on MIT's Lisp Machine, but will likely have most of it up tonight), but I would think it would be easier to perhaps do some small comparisons in the individual sections -- I'll be pointing out some differences in Genera and C++ OS's in OO memory, for example -- and then make some more broad strokes in the conclusion encompassing two or more of our chosen OS's and C/C++.

--[[User:ScottG|ScottG]] 19:19, 12 October 2010 (UTC)

Hi all. I'm gradually posting the sections that I finished so far I'd love to hear your thoughts and comments.

Anil also mentioned an important note on our question, we have to compare these operating systems to the ones developed using C and C++. Are we going to do that in the conclusion section? because so far we are not answering the second half of the question.

As for the Oberon, I just did a quick read in Wiki and it says that its written in oberon programming language. But it says its based on a modified version of Modula-2 and they don't mention modula-3, can we still talk about this OS? I cant really start on that today I have a chemistery midterm tomorrow morning, and tomorrow I'm going to finish the rest of SPIN sections.

--[[User:Ymoussou|Youcef M.]] 19:00, 12 October 2010 (UTC)

Thanks for the link Anil! For the group: I asked Anil a couple of questions after class today, and another OS he had in mind was [http://en.wikipedia.org/wiki/Oberon_(operating_system) Oberon], invented by the creator of Modula-3. I don't know if there's more to find about this than there is about SPIN but I've got my hands full for now.

--[[User:Jjpwilso|Jjpwilso]] 18:29, 12 October 2010 (UTC)

Rather than Squeak I was thinking about Smalltalk-80. Here's a [http://portal.acm.org/citation.cfm?id=273&dl=GUIDE,ACM book on Smalltalk] that's available online in the ACM digital library. Just the preface should tell you everything you need to know. [[User:Soma|Anil]] 03:15, 12 October 2010 (UTC)

Great work on the Java section. I might toss in a bit on the problems section about cross-platform compatibility once I get done with my part.

--[[User:Jjpwilso|Jjpwilso]] 23:57, 10 October 2010 (UTC)

I've posted what I have written so far for the Java section, if anyone has any suggestion/corrections feel free to post them.
EDIT: I've added the other sections of the Java based operating system.

--[[User:Selliot3|Selliot3]] 16:50, 10 October 2010 (UTC)

Re: Motivation. I had Smalltalk in mind when I roughed out the headings and it's pretty much what you suggested. But the headings are only a guideline. If you prefer a different structure for your sections feel free to improvise. As for format I am assuming an essay style.

Re: SPIN. The ACM site has some stuff. You'll need your student card handy to get through the Carleton Library proxy.

Here are a couple of links (you can find a TON more if you search for SPIN at the top of the portal):

[http://portal.acm.org.proxy.library.carleton.ca/citation.cfm?id=380921.380940&coll=ACM&dl=ACM&CFID=108110330&CFTOKEN=12401653 Distributed LTL model-checking in SPIN]

[http://portal.acm.org.proxy.library.carleton.ca/citation.cfm?id=380921.380935&coll=ACM&dl=ACM&CFID=108110330&CFTOKEN=12401653 Using SPIN for feature interaction analysis—a case study]

--[[User:Jjpwilso|Jjpwilso]] 16:25, 10 October 2010 (UTC)

This is all I could find on SPIN

SPIN-An extensible microkernel for application-specific operating system devices [http://www.dtic.mil/cgi-bin/GetTRDoc?Location=U2&doc=GetTRDoc.pdf&AD=ADA293537]

Extensibility, Safety and Performance in the SPIN Operating System [http://cseweb.ucsd.edu/~savage/papers/Sosp95.pdf]

SPIN-Operating System [http://cs-pub.bu.edu/fac/richwest/cs591_w1/notes/spin.pdf]

Lecture 9: SPIN operating system [http://www.youtube.com/watch?v=YE9uztJ_CFg]

--[[User:Ymoussou|Youcef M.]] 16:06, 10 October 2010 (UTC)

What is meant by "Motivation"? Would that be motivation to use the language for an operating system? Also, what format should we be doing this in? I'm pretty much writing in an essay style for the overview to explain all of the operating systems in Java with an introduction and a paragraph for each of the systems. Then, I would fill out a paragraph or two for Motivation, Problems, etc. Does that seem fine?

--[[User:Selliot3|Selliot3]] 15:13, 10 October 2010 (UTC)

Here's a link to the main [http://www-spin.cs.washington.edu/ SPIN website].

--[[User:Jjpwilso|Jjpwilso]] 16:40, 9 October 2010 (UTC)

I'll start right away, but the reference link doesn't work...

--Youcef M. 15:06, 9 October 2010 (UTC)

Welcome, Youcef. It would probably be best if you focused on one operating system for now. Nobody has claimed SPIN yet, the OS in Modula-3. Do you think you could dig into that? There's a good reference below.

--[[User:Jjpwilso|Jjpwilso]] 15:02, 9 October 2010 (UTC)

Hey guys I'm in the group, sorry for not adding something yet. I've been working on a table which has all the operating systems in those languages and comparing them to each other. But it was harder than I thought, I was trying to find where the OS's are similar and where they are different. It got a little bit long and random; I can find a lot of info on one OS but almost none on the other. Do you guys think its worth the trouble to finish it or should just forget about and keep up with you guys?

--Youcef M. 14:41, 9 October 2010 (UTC)

Particular to Squeak: [http://portal.acm.org.proxy.library.carleton.ca/ft_gateway.cfm?id=263754&type=pdf&coll=ACM&dl=ACM&CFID=107940135&CFTOKEN=78771329 Back to the Future - The Story of Squeak, A Practical Smalltalk Written in Itself]

--[[User:Jjpwilso|Jjpwilso]] 13:29, 9 October 2010 (UTC)

From an interview with Alan Kay, founder of Smalltalk, I tracked down a very useful history:
[http://portal.acm.org.proxy.library.carleton.ca/results.cfm?coll=ACM&dl=ACM&CFID=107940135&CFTOKEN=78771329 The Early History of Smalltalk]. There happen to be some important foundational points in here (with references) that relate to other systems as well. For instance he explains how LISP was a vital part of how he came to understand the power of languages. Warning: it's quite long and I don't understand half of it.

--[[User:Jjpwilso|Jjpwilso]] 13:02, 9 October 2010 (UTC)

I'd be fine doing LISP, among throwing out anything good for the other languages I happen to come across.

--[[User:ScottG|ScottG]] 21:27, 8 October 2010 (UTC)

Okay, lets all put down our preferences here and set a reasonable deadline of Saturday at 23:59 for a cutoff. Smalltalk would be my top choice. Of course any contributions to any language will be welcome.

--[[User:Jjpwilso|Jjpwilso]] 16:07, 8 October 2010 (UTC)

I would love to do the Java section. I`ve done quite a bit of development on Android and have also read a complete book on how the Android operating system works. Of course, there are other OS`s to look at but I`m a big fan of Android so I`m always happy to write about it haha.

--[[User:Selliot3|Selliot3]] 15:44, 8 October 2010 (UTC)

I recommend we use the habit of putting more recent comments at the top in case this gets to be a longish list. I've gone ahead and stubbed out a proposed structure. Please comment (thumbs up/down). If we all agree we can start dividing up the parts so we don't do the same work. We're lucky as a team to have such a nicely partitioned essay to write!

--[[User:Jjpwilso|Jjpwilso]] 13:23, 8 October 2010 (UTC)

Genera (LISP) - http://en.wikipedia.org/wiki/Genera_(operating_system) <-- only for a reference for now 
SPIN (Modula) - http://www-spin.cs.washington.edu%2Fexternal%2Foverview.html 
Squeak (SmallTalk) - http://en.wikipedia.org/wiki/Squeak <-- only a reference, says it's a programming language but can be used as an OS 
JavaOS (Java) - http://java.sun.com/developer/products/JavaOS/ 

--[[User:Selliot3|Selliot3]] 00:16, 6 October 2010 (UTC) or Charles

Not a great site, but gives a nice breakdown of the main points of Squeak - http://www.visoracle.com/squeak/overview.html 
And a much longer, more in-depth Squeak page - http://www.cosc.canterbury.ac.nz/wolfgang.kreutzer/cosc205/smalltalk1.html 
A nice breakdown for JavaOS - http://www.operating-system.org/betriebssystem/_english/bs-javaos.htm 
And a very nice PDF for Genera - http://ieeexplore.ieee.org/xpls/abs_all.jsp?arnumber=183015&tag=1 
--[[User:ScottG|ScottG]] 13:08, 6 October 2010 (UTC)

For Java section: [http://developer.android.com/guide/basics/what-is-android.html What is Android] shows the limited role of DVM (Android's JVM). 
--[[User:Jjpwilso|Jjpwilso]] 14:31, 7 October 2010 (UTC)

Talk:COMP 3000 Essay 1 2010 Question 4

2010-10-13T15:37:18Z

ScottG: /* Discussion */

== Discussion ==

Okay, I've basically got the Lisp section done. Gonna probably go back and tweak it, but at least it's there. And I added in what I used as references in the References section as per MLA style.

I can take a look at writing up something for the C/C++ part as well, just not sure how much I'll be able to get in the time I've got to spare between other courses right now. But I'll certainly try.

--[[User:ScottG|ScottG]] 15:37, 13 October 2010 (UTC)

Could somebody add a bit in the introduction on what it means to be an operating system written in C/C++? One focus should probably be the notion of process as hinted by Anil. There are probably other distinctions that can be dredged up too.

--[[User:Jjpwilso|Jjpwilso]] 02:57, 13 October 2010 (UTC)

Got some stuff up, rough copy only. Meant to get more done, but family stuff came up. More to come tomorrow.

--[[User:ScottG|ScottG]] 02:26, 13 October 2010 (UTC)

Right then, I'm on it.

--[[User:Mkugler|Mkugler]] 01:19, 13 October 2010 (UTC)

Hi MK, and welcome to the group. Anil mentioned Oberon just today, which is apparently another OS based on a cousin of modula-3. If you could find a way to extend the Modula-3 section with Oberon, perhaps with your own subsection (Youcef has already started with a SPIN section) that should help us round things up nicely. Note the goal is to compare capabilities with C/C++, so feel free to take a global view for thematic consistency too. I'll be doing a bit more in this respect on the Smalltalk section. As Anil said in lecture today, it should hold together as an essay even without the wiki-ish headings.

--[[User:Jjpwilso|Jjpwilso]] 01:07, 13 October 2010 (UTC)

Hey guys. I'm a bit late to the punch on this as I've been preoccupied with a ton of other stuff. I've read through what you've all done thus far and frankly think it's phenomenal, which brings me to my quandry. I wasn't here when you all laid claim to the various components of the essay and am not entirely certain where my efforts should be directed. I noticed that LISP so far is empty, but that it was claimed by ScottG on the 8th.

Is there anywhere in particular where you would like me to work? I'm committed to spending the better part of the next 48 hours entirely on this, so I can put together anything remaining that's needed. If you guys can't get back to me, I'll just expand on whatever I can find more information on.

--[[User:Mkugler|Mkugler]] 23:16, 12 October 2010 (UTC)

The SPIN work is looking good Youcef. Note: please try to put links to your sources in the text so we can see where your ideas are coming from.

--[[User:Jjpwilso|Jjpwilso]] 20:45, 12 October 2010 (UTC)

Anil gave me another clue into how he was thinking of comparisons between these OSes and C/C++. For Smalltalk at least the central theme mentions nothing about processes. Smalltalk is about objects, methods, and messages rather than the traditional C notion of processes manipulating data. This distinction or something similar to it may be useful when looking at other operating systems we're exploring.

--[[User:Jjpwilso|Jjpwilso]] 20:42, 12 October 2010 (UTC)

I've got some small amount of comparison in mine (haven't posted it, since I'm still trying to compile info on MIT's Lisp Machine, but will likely have most of it up tonight), but I would think it would be easier to perhaps do some small comparisons in the individual sections -- I'll be pointing out some differences in Genera and C++ OS's in OO memory, for example -- and then make some more broad strokes in the conclusion encompassing two or more of our chosen OS's and C/C++.

--[[User:ScottG|ScottG]] 19:19, 12 October 2010 (UTC)

Hi all. I'm gradually posting the sections that I finished so far I'd love to hear your thoughts and comments.

Anil also mentioned an important note on our question, we have to compare these operating systems to the ones developed using C and C++. Are we going to do that in the conclusion section? because so far we are not answering the second half of the question.

As for the Oberon, I just did a quick read in Wiki and it says that its written in oberon programming language. But it says its based on a modified version of Modula-2 and they don't mention modula-3, can we still talk about this OS? I cant really start on that today I have a chemistery midterm tomorrow morning, and tomorrow I'm going to finish the rest of SPIN sections.

--[[User:Ymoussou|Youcef M.]] 19:00, 12 October 2010 (UTC)

Thanks for the link Anil! For the group: I asked Anil a couple of questions after class today, and another OS he had in mind was [http://en.wikipedia.org/wiki/Oberon_(operating_system) Oberon], invented by the creator of Modula-3. I don't know if there's more to find about this than there is about SPIN but I've got my hands full for now.

--[[User:Jjpwilso|Jjpwilso]] 18:29, 12 October 2010 (UTC)

Rather than Squeak I was thinking about Smalltalk-80. Here's a [http://portal.acm.org/citation.cfm?id=273&dl=GUIDE,ACM book on Smalltalk] that's available online in the ACM digital library. Just the preface should tell you everything you need to know. [[User:Soma|Anil]] 03:15, 12 October 2010 (UTC)

Great work on the Java section. I might toss in a bit on the problems section about cross-platform compatibility once I get done with my part.

--[[User:Jjpwilso|Jjpwilso]] 23:57, 10 October 2010 (UTC)

I've posted what I have written so far for the Java section, if anyone has any suggestion/corrections feel free to post them.
EDIT: I've added the other sections of the Java based operating system.

--[[User:Selliot3|Selliot3]] 16:50, 10 October 2010 (UTC)

Re: Motivation. I had Smalltalk in mind when I roughed out the headings and it's pretty much what you suggested. But the headings are only a guideline. If you prefer a different structure for your sections feel free to improvise. As for format I am assuming an essay style.

Re: SPIN. The ACM site has some stuff. You'll need your student card handy to get through the Carleton Library proxy.

Here are a couple of links (you can find a TON more if you search for SPIN at the top of the portal):

[http://portal.acm.org.proxy.library.carleton.ca/citation.cfm?id=380921.380940&coll=ACM&dl=ACM&CFID=108110330&CFTOKEN=12401653 Distributed LTL model-checking in SPIN]

[http://portal.acm.org.proxy.library.carleton.ca/citation.cfm?id=380921.380935&coll=ACM&dl=ACM&CFID=108110330&CFTOKEN=12401653 Using SPIN for feature interaction analysis—a case study]

--[[User:Jjpwilso|Jjpwilso]] 16:25, 10 October 2010 (UTC)

This is all I could find on SPIN

SPIN-An extensible microkernel for application-specific operating system devices [http://www.dtic.mil/cgi-bin/GetTRDoc?Location=U2&doc=GetTRDoc.pdf&AD=ADA293537]

Extensibility, Safety and Performance in the SPIN Operating System [http://cseweb.ucsd.edu/~savage/papers/Sosp95.pdf]

SPIN-Operating System [http://cs-pub.bu.edu/fac/richwest/cs591_w1/notes/spin.pdf]

Lecture 9: SPIN operating system [http://www.youtube.com/watch?v=YE9uztJ_CFg]

--[[User:Ymoussou|Youcef M.]] 16:06, 10 October 2010 (UTC)

What is meant by "Motivation"? Would that be motivation to use the language for an operating system? Also, what format should we be doing this in? I'm pretty much writing in an essay style for the overview to explain all of the operating systems in Java with an introduction and a paragraph for each of the systems. Then, I would fill out a paragraph or two for Motivation, Problems, etc. Does that seem fine?

--[[User:Selliot3|Selliot3]] 15:13, 10 October 2010 (UTC)

Here's a link to the main [http://www-spin.cs.washington.edu/ SPIN website].

--[[User:Jjpwilso|Jjpwilso]] 16:40, 9 October 2010 (UTC)

I'll start right away, but the reference link doesn't work...

--Youcef M. 15:06, 9 October 2010 (UTC)

Welcome, Youcef. It would probably be best if you focused on one operating system for now. Nobody has claimed SPIN yet, the OS in Modula-3. Do you think you could dig into that? There's a good reference below.

--[[User:Jjpwilso|Jjpwilso]] 15:02, 9 October 2010 (UTC)

Hey guys I'm in the group, sorry for not adding something yet. I've been working on a table which has all the operating systems in those languages and comparing them to each other. But it was harder than I thought, I was trying to find where the OS's are similar and where they are different. It got a little bit long and random; I can find a lot of info on one OS but almost none on the other. Do you guys think its worth the trouble to finish it or should just forget about and keep up with you guys?

--Youcef M. 14:41, 9 October 2010 (UTC)

Particular to Squeak: [http://portal.acm.org.proxy.library.carleton.ca/ft_gateway.cfm?id=263754&type=pdf&coll=ACM&dl=ACM&CFID=107940135&CFTOKEN=78771329 Back to the Future - The Story of Squeak, A Practical Smalltalk Written in Itself]

--[[User:Jjpwilso|Jjpwilso]] 13:29, 9 October 2010 (UTC)

From an interview with Alan Kay, founder of Smalltalk, I tracked down a very useful history:
[http://portal.acm.org.proxy.library.carleton.ca/results.cfm?coll=ACM&dl=ACM&CFID=107940135&CFTOKEN=78771329 The Early History of Smalltalk]. There happen to be some important foundational points in here (with references) that relate to other systems as well. For instance he explains how LISP was a vital part of how he came to understand the power of languages. Warning: it's quite long and I don't understand half of it.

--[[User:Jjpwilso|Jjpwilso]] 13:02, 9 October 2010 (UTC)

I'd be fine doing LISP, among throwing out anything good for the other languages I happen to come across.

--[[User:ScottG|ScottG]] 21:27, 8 October 2010 (UTC)

Okay, lets all put down our preferences here and set a reasonable deadline of Saturday at 23:59 for a cutoff. Smalltalk would be my top choice. Of course any contributions to any language will be welcome.

--[[User:Jjpwilso|Jjpwilso]] 16:07, 8 October 2010 (UTC)

I would love to do the Java section. I`ve done quite a bit of development on Android and have also read a complete book on how the Android operating system works. Of course, there are other OS`s to look at but I`m a big fan of Android so I`m always happy to write about it haha.

--[[User:Selliot3|Selliot3]] 15:44, 8 October 2010 (UTC)

I recommend we use the habit of putting more recent comments at the top in case this gets to be a longish list. I've gone ahead and stubbed out a proposed structure. Please comment (thumbs up/down). If we all agree we can start dividing up the parts so we don't do the same work. We're lucky as a team to have such a nicely partitioned essay to write!

--[[User:Jjpwilso|Jjpwilso]] 13:23, 8 October 2010 (UTC)

Genera (LISP) - http://en.wikipedia.org/wiki/Genera_(operating_system) <-- only for a reference for now 
SPIN (Modula) - http://www-spin.cs.washington.edu%2Fexternal%2Foverview.html 
Squeak (SmallTalk) - http://en.wikipedia.org/wiki/Squeak <-- only a reference, says it's a programming language but can be used as an OS 
JavaOS (Java) - http://java.sun.com/developer/products/JavaOS/ 

--[[User:Selliot3|Selliot3]] 00:16, 6 October 2010 (UTC) or Charles

Not a great site, but gives a nice breakdown of the main points of Squeak - http://www.visoracle.com/squeak/overview.html 
And a much longer, more in-depth Squeak page - http://www.cosc.canterbury.ac.nz/wolfgang.kreutzer/cosc205/smalltalk1.html 
A nice breakdown for JavaOS - http://www.operating-system.org/betriebssystem/_english/bs-javaos.htm 
And a very nice PDF for Genera - http://ieeexplore.ieee.org/xpls/abs_all.jsp?arnumber=183015&tag=1 
--[[User:ScottG|ScottG]] 13:08, 6 October 2010 (UTC)

For Java section: [http://developer.android.com/guide/basics/what-is-android.html What is Android] shows the limited role of DVM (Android's JVM). 
--[[User:Jjpwilso|Jjpwilso]] 14:31, 7 October 2010 (UTC)

Talk:COMP 3000 Essay 1 2010 Question 4

2010-10-13T15:37:08Z

ScottG: /* Discussion */

== Discussion ==

Okay, I've basically got the Lisp section done. Gonna probably go back and tweak it, but at least it's there. And I added in what I used as references in the References section as per MLA style.

I can take a look at writing up something for the C/C++ part as well, just not sure how much I'll be able to get in the time I've got to spare between other courses right now. But I'll certainly try.
--[[User:ScottG|ScottG]] 15:37, 13 October 2010 (UTC)

Could somebody add a bit in the introduction on what it means to be an operating system written in C/C++? One focus should probably be the notion of process as hinted by Anil. There are probably other distinctions that can be dredged up too.

--[[User:Jjpwilso|Jjpwilso]] 02:57, 13 October 2010 (UTC)

Got some stuff up, rough copy only. Meant to get more done, but family stuff came up. More to come tomorrow.

--[[User:ScottG|ScottG]] 02:26, 13 October 2010 (UTC)

Right then, I'm on it.

--[[User:Mkugler|Mkugler]] 01:19, 13 October 2010 (UTC)

Hi MK, and welcome to the group. Anil mentioned Oberon just today, which is apparently another OS based on a cousin of modula-3. If you could find a way to extend the Modula-3 section with Oberon, perhaps with your own subsection (Youcef has already started with a SPIN section) that should help us round things up nicely. Note the goal is to compare capabilities with C/C++, so feel free to take a global view for thematic consistency too. I'll be doing a bit more in this respect on the Smalltalk section. As Anil said in lecture today, it should hold together as an essay even without the wiki-ish headings.

--[[User:Jjpwilso|Jjpwilso]] 01:07, 13 October 2010 (UTC)

Hey guys. I'm a bit late to the punch on this as I've been preoccupied with a ton of other stuff. I've read through what you've all done thus far and frankly think it's phenomenal, which brings me to my quandry. I wasn't here when you all laid claim to the various components of the essay and am not entirely certain where my efforts should be directed. I noticed that LISP so far is empty, but that it was claimed by ScottG on the 8th.

Is there anywhere in particular where you would like me to work? I'm committed to spending the better part of the next 48 hours entirely on this, so I can put together anything remaining that's needed. If you guys can't get back to me, I'll just expand on whatever I can find more information on.

--[[User:Mkugler|Mkugler]] 23:16, 12 October 2010 (UTC)

The SPIN work is looking good Youcef. Note: please try to put links to your sources in the text so we can see where your ideas are coming from.

--[[User:Jjpwilso|Jjpwilso]] 20:45, 12 October 2010 (UTC)

Anil gave me another clue into how he was thinking of comparisons between these OSes and C/C++. For Smalltalk at least the central theme mentions nothing about processes. Smalltalk is about objects, methods, and messages rather than the traditional C notion of processes manipulating data. This distinction or something similar to it may be useful when looking at other operating systems we're exploring.

--[[User:Jjpwilso|Jjpwilso]] 20:42, 12 October 2010 (UTC)

I've got some small amount of comparison in mine (haven't posted it, since I'm still trying to compile info on MIT's Lisp Machine, but will likely have most of it up tonight), but I would think it would be easier to perhaps do some small comparisons in the individual sections -- I'll be pointing out some differences in Genera and C++ OS's in OO memory, for example -- and then make some more broad strokes in the conclusion encompassing two or more of our chosen OS's and C/C++.

--[[User:ScottG|ScottG]] 19:19, 12 October 2010 (UTC)

Hi all. I'm gradually posting the sections that I finished so far I'd love to hear your thoughts and comments.

Anil also mentioned an important note on our question, we have to compare these operating systems to the ones developed using C and C++. Are we going to do that in the conclusion section? because so far we are not answering the second half of the question.

As for the Oberon, I just did a quick read in Wiki and it says that its written in oberon programming language. But it says its based on a modified version of Modula-2 and they don't mention modula-3, can we still talk about this OS? I cant really start on that today I have a chemistery midterm tomorrow morning, and tomorrow I'm going to finish the rest of SPIN sections.

--[[User:Ymoussou|Youcef M.]] 19:00, 12 October 2010 (UTC)

Thanks for the link Anil! For the group: I asked Anil a couple of questions after class today, and another OS he had in mind was [http://en.wikipedia.org/wiki/Oberon_(operating_system) Oberon], invented by the creator of Modula-3. I don't know if there's more to find about this than there is about SPIN but I've got my hands full for now.

--[[User:Jjpwilso|Jjpwilso]] 18:29, 12 October 2010 (UTC)

Rather than Squeak I was thinking about Smalltalk-80. Here's a [http://portal.acm.org/citation.cfm?id=273&dl=GUIDE,ACM book on Smalltalk] that's available online in the ACM digital library. Just the preface should tell you everything you need to know. [[User:Soma|Anil]] 03:15, 12 October 2010 (UTC)

Great work on the Java section. I might toss in a bit on the problems section about cross-platform compatibility once I get done with my part.

--[[User:Jjpwilso|Jjpwilso]] 23:57, 10 October 2010 (UTC)

I've posted what I have written so far for the Java section, if anyone has any suggestion/corrections feel free to post them.
EDIT: I've added the other sections of the Java based operating system.

--[[User:Selliot3|Selliot3]] 16:50, 10 October 2010 (UTC)

Re: Motivation. I had Smalltalk in mind when I roughed out the headings and it's pretty much what you suggested. But the headings are only a guideline. If you prefer a different structure for your sections feel free to improvise. As for format I am assuming an essay style.

Re: SPIN. The ACM site has some stuff. You'll need your student card handy to get through the Carleton Library proxy.

Here are a couple of links (you can find a TON more if you search for SPIN at the top of the portal):

[http://portal.acm.org.proxy.library.carleton.ca/citation.cfm?id=380921.380940&coll=ACM&dl=ACM&CFID=108110330&CFTOKEN=12401653 Distributed LTL model-checking in SPIN]

[http://portal.acm.org.proxy.library.carleton.ca/citation.cfm?id=380921.380935&coll=ACM&dl=ACM&CFID=108110330&CFTOKEN=12401653 Using SPIN for feature interaction analysis—a case study]

--[[User:Jjpwilso|Jjpwilso]] 16:25, 10 October 2010 (UTC)

This is all I could find on SPIN

SPIN-An extensible microkernel for application-specific operating system devices [http://www.dtic.mil/cgi-bin/GetTRDoc?Location=U2&doc=GetTRDoc.pdf&AD=ADA293537]

Extensibility, Safety and Performance in the SPIN Operating System [http://cseweb.ucsd.edu/~savage/papers/Sosp95.pdf]

SPIN-Operating System [http://cs-pub.bu.edu/fac/richwest/cs591_w1/notes/spin.pdf]

Lecture 9: SPIN operating system [http://www.youtube.com/watch?v=YE9uztJ_CFg]

--[[User:Ymoussou|Youcef M.]] 16:06, 10 October 2010 (UTC)

What is meant by "Motivation"? Would that be motivation to use the language for an operating system? Also, what format should we be doing this in? I'm pretty much writing in an essay style for the overview to explain all of the operating systems in Java with an introduction and a paragraph for each of the systems. Then, I would fill out a paragraph or two for Motivation, Problems, etc. Does that seem fine?

--[[User:Selliot3|Selliot3]] 15:13, 10 October 2010 (UTC)

Here's a link to the main [http://www-spin.cs.washington.edu/ SPIN website].

--[[User:Jjpwilso|Jjpwilso]] 16:40, 9 October 2010 (UTC)

I'll start right away, but the reference link doesn't work...

--Youcef M. 15:06, 9 October 2010 (UTC)

Welcome, Youcef. It would probably be best if you focused on one operating system for now. Nobody has claimed SPIN yet, the OS in Modula-3. Do you think you could dig into that? There's a good reference below.

--[[User:Jjpwilso|Jjpwilso]] 15:02, 9 October 2010 (UTC)

Hey guys I'm in the group, sorry for not adding something yet. I've been working on a table which has all the operating systems in those languages and comparing them to each other. But it was harder than I thought, I was trying to find where the OS's are similar and where they are different. It got a little bit long and random; I can find a lot of info on one OS but almost none on the other. Do you guys think its worth the trouble to finish it or should just forget about and keep up with you guys?

--Youcef M. 14:41, 9 October 2010 (UTC)

Particular to Squeak: [http://portal.acm.org.proxy.library.carleton.ca/ft_gateway.cfm?id=263754&type=pdf&coll=ACM&dl=ACM&CFID=107940135&CFTOKEN=78771329 Back to the Future - The Story of Squeak, A Practical Smalltalk Written in Itself]

--[[User:Jjpwilso|Jjpwilso]] 13:29, 9 October 2010 (UTC)

From an interview with Alan Kay, founder of Smalltalk, I tracked down a very useful history:
[http://portal.acm.org.proxy.library.carleton.ca/results.cfm?coll=ACM&dl=ACM&CFID=107940135&CFTOKEN=78771329 The Early History of Smalltalk]. There happen to be some important foundational points in here (with references) that relate to other systems as well. For instance he explains how LISP was a vital part of how he came to understand the power of languages. Warning: it's quite long and I don't understand half of it.

--[[User:Jjpwilso|Jjpwilso]] 13:02, 9 October 2010 (UTC)

I'd be fine doing LISP, among throwing out anything good for the other languages I happen to come across.

--[[User:ScottG|ScottG]] 21:27, 8 October 2010 (UTC)

Okay, lets all put down our preferences here and set a reasonable deadline of Saturday at 23:59 for a cutoff. Smalltalk would be my top choice. Of course any contributions to any language will be welcome.

--[[User:Jjpwilso|Jjpwilso]] 16:07, 8 October 2010 (UTC)

I would love to do the Java section. I`ve done quite a bit of development on Android and have also read a complete book on how the Android operating system works. Of course, there are other OS`s to look at but I`m a big fan of Android so I`m always happy to write about it haha.

--[[User:Selliot3|Selliot3]] 15:44, 8 October 2010 (UTC)

I recommend we use the habit of putting more recent comments at the top in case this gets to be a longish list. I've gone ahead and stubbed out a proposed structure. Please comment (thumbs up/down). If we all agree we can start dividing up the parts so we don't do the same work. We're lucky as a team to have such a nicely partitioned essay to write!

--[[User:Jjpwilso|Jjpwilso]] 13:23, 8 October 2010 (UTC)

Genera (LISP) - http://en.wikipedia.org/wiki/Genera_(operating_system) <-- only for a reference for now 
SPIN (Modula) - http://www-spin.cs.washington.edu%2Fexternal%2Foverview.html 
Squeak (SmallTalk) - http://en.wikipedia.org/wiki/Squeak <-- only a reference, says it's a programming language but can be used as an OS 
JavaOS (Java) - http://java.sun.com/developer/products/JavaOS/ 

--[[User:Selliot3|Selliot3]] 00:16, 6 October 2010 (UTC) or Charles

Not a great site, but gives a nice breakdown of the main points of Squeak - http://www.visoracle.com/squeak/overview.html 
And a much longer, more in-depth Squeak page - http://www.cosc.canterbury.ac.nz/wolfgang.kreutzer/cosc205/smalltalk1.html 
A nice breakdown for JavaOS - http://www.operating-system.org/betriebssystem/_english/bs-javaos.htm 
And a very nice PDF for Genera - http://ieeexplore.ieee.org/xpls/abs_all.jsp?arnumber=183015&tag=1 
--[[User:ScottG|ScottG]] 13:08, 6 October 2010 (UTC)

For Java section: [http://developer.android.com/guide/basics/what-is-android.html What is Android] shows the limited role of DVM (Android's JVM). 
--[[User:Jjpwilso|Jjpwilso]] 14:31, 7 October 2010 (UTC)

COMP 3000 Essay 1 2010 Question 4

2010-10-13T15:34:21Z

ScottG: /* References */

=Question=

What "operating systems" have been implemented in the following languages: LISP, Modula-3, Smalltalk, Java? To what extent do these systems match the capabilities of operating systems implemented in C and C++?

=Team Note (to be removed by delivery date)=

Please use the [[Talk:COMP_3000_Essay_1_2010_Question_4|discussion page]] for any planning and comments.

=Answer=

== Introduction ==

Not so long ago people believed the Earth was a flat world at the center of the universe. This essay addresses a more recent falsehood: that all operating systems are written in assembly language and C. It's not surprising that students of computing in this century would genuflect at the academic altars of Kernighan & Ritchie. After all we grew up with our computer worlds already pre-formed into the conceptual continents of Apple OS, UNIX, and Windows. The more historically curious among us are vaguely aware that other island cultures do exist but they represent civilizations defeated in the marketplace. Explorations into these ancient worlds resemble documentaries about archeologists decoding rediscovered languages etched in stone. But scratch the surface of any of our so-called modern operating systems and you'll find echoes of these ancient languages in our own familiar worlds. Ellen Ullman said it best when she wrote, <blockquote>''We build our computer systems like we build our cities: over time, without a plan, on top of ruins.''</blockquote>

In the sections below we present our explorations into a few truly foundational operating systems. We will also see some brand new ones that prove we stand, as one twelfth century scholar put it, [http://en.wikipedia.org/wiki/Standing_on_the_shoulders_of_giants on the shoulders of giants].

The following is a short list of operating systems written partially or completely with the given language. We will go into more detail in the language-specific sections below.

{| class="wikitable" style="text-align:center" border="1"
|+ '''Operating Systems By Language'''
|-
!width="15%"|Language
!width="85%"|OS List
|-
! Lisp
| MIT's Lisp Machines, Genera
|-
! Modula-3
| SPIN OS
|-
! Smalltalk
| Smalltalk-80 on Xerox Alto, Squeak
|-
! Java
| JavaOS, JNode, JX, Android
|}

==Lisp Based==
===Overview===
Lisp is the second oldest programming languages, established in the late 1960's as a list-processing language. It started out being perfect for math but when it came to programming with it, it left a lot to be desired. Since then there have been a number of different versions of it, from the first Lisp – called “pure Lisp” – to Scheme and Common Lisp. Unlike most object-oriented languages which are focused on classes and instances among other things, Lisp was initially focused more on functions, in which functions call other functions, though later versions of Lisp did eventually add in classes and other typical object-oriented features. It was after this that Genera was created, an operating system written entirely in Lisp, and developed from an earlier operating system on MIT's Lisp Machine.

The Lisp Machine project in began in 1974, where Richard Greenblatt and Thomas Knight, programmers at MIT, designed a computer for general use that was designed for a single user, in which the operating system was programmed entirely in Lisp. It was designed to be completely open to the user, so any changes the user wanted to make could be done during run-time. It was also one of the first systems to be programmed in a 32-bit architecture, making it far more versatile than a number of other operating systems at the time. Despite this, however, the first Lisp Machine was quite basic compared to later iterations, namely Genera.

===Motivation===
Genera is an evolution of the initial Lisp Machine operating system, and as such improved upon many of the basic features of the system. Genera was the first object-oriented operating system, making it stand out among the already well-known Lisp Machines, especially given the fact that it isn't a composition of languages like other operating systems – most using the primary language for the operating system and another language, such as assembly, to deal with hardware directly – but written entirely in Lisp – any of five different dialects of the language – including the lowest levels of the operating system that interact with hardware due to its effective lack of a kernel. Not having to deal with a kernel allows Genera to be very powerful and efficient in certain areas, most especially in the most complex applications such as those dealing with intelligent CAD and graphics, though when given very simple, very routine applications or processes it is much less efficient than other operating systems.

===Achievements===
Another primary difference from other operating systems is that Genera is a fully open system like the first Lisp Machines. Having an open system has its positive and negative aspects. Among the foremost positive aspects is that the user is in control and not left to the whims of the operating system as is common in non-open systems – if the user doesn't like how something is happening, they can simply go in and change it from happening that way again – and allows for very quick prototyping, not needing to wait to compile every little change. Also, due to utilizing very lightweight objects and the fact that everything is in a single address space rather than split across multiple spaces greatly increases efficiency, though again mainly in non-simple tasks.

Like operating systems written in C/C++, Genera has multiple inheritance and automatic garbage collection. Unlike C/C++, however, Genera uses object-oriented memory. This gives Genera a very useful feature that many other systems cannot do, which is that, given a memory address, the system is able to provide the start address, size, and the type of object in that memory location, which increases efficiency. Even the way files are accessed is very different from other operating systems, as it uses a generic file access system; in a generic file access system, rather than following a typical structure of keeping the commands needed for local and networked files different, the commands are the same, meaning that the system essentially acts like a file on a system on the other side of the world is a local file.

===Problems===
Not everything is great with an open system, however, as there are definite security concerns: with an open system, the user can change anything, and programs can interact with other programs and change anything, meaning that if a virus were unleashed on a Genera system it could be catastrophic. To counter this problem Genera systems are protected by a very simple method: keeping the physical system itself out of reach of all but authorized users and behind locked doors. To compare to other operating systems, such as those written in C/C++, it is generally less secure because of the open system, though they are both equally at risk when installing software, as both systems are completely open at that specific junction. Genera also has issues with modularity, as it allows for something to be called even when it is not supposed to be able to be called because, as it is an open system, there is nothing really stopping this from happening. Some versions of Genera and Genera applications are also very well-documented and run quite smoothly, but others are poorly documented and run quite slowly as they are built on top of older versions without any real plan beyond adding on an extra feature here or there over and over again.

===Current Status===
Genera and Lisp Machines, while still being used in a select few locations, are not currently being developed, as their time has passed. Their legacy still lives on, however, in the object-oriented operating systems still in use today.

==Modula-3 Based==
===Overview===

An idea came to mind. A question was proposed. Can an operating system have extensibility, safety, and good performance? A group of computer scientists from Washington University took on this question and tried to come up with an answer. That’s how SPIN operating system was created. SPIN is an operating system that blends the user-level with the kernel level. The main feature is that the kernel can be extended using modules that implement interfaces to meet the applications needs to optimise performance and safety. The programming language used is Modula-3, and the reason for using this language is for its type safe properties like interfaces, extension, and its automatic storage management.

===Motivation===

The team had to meet three important features to make this work, a Flexible kernel with safe extensions and a good overall performance. The goal was to create a specialized operating system that can run a range of applications without sacrificing safety or performance. This system would allow the user programs and applications to manipulate and change the system’s interface to load and access the data or memory needed safely and with a good overall performance. This was possible through the type safe extensions of Modula-3.

===Achievements===

* They pulled it off

===Problems===

* Design issues

===Current Status===

* Still under research

==Smalltalk Based==
===Overview===

<blockquote>The best way to predict the future is to invent it. -- Alan Kay</blockquote>

If you are reading this paper on a personal computer, and it has a GUI with overlapping windows, desktop icons, and a mouse pointer then you owe a debt to a group of researchers led by Alan Kay at Xerox's Palo Alto Research Center, or Xerox PARC. Many of those ideas had appeared elsewhere in one form or another, but the first time they came together in a demonstrable and portable form was in the early 1970s at Xerox on a machine called the Alto [http://en.wikipedia.org/wiki/Xerox_Alto]. Their example of a working personal computer was to be the inspiration that launched Apple into the history books.

===Motivation===

Searching for operating systems written in Smalltalk is an exercise in recursion. The Smalltalk OS was written in -- what else -- Smalltalk. But Alan Kay's Learning Research Group (LRG) didn't just set out to write a clever new language that could bootstrap its own environment. Not only were they in California but they had also just survived the 1960s. Their goal was to produce an entirely new learning environment to "amplify human reach and bring new ways of thinking to a faltering civilization that desperately needed it." [http://www.smalltalk.org/smalltalk/TheEarlyHistoryOfSmalltalk_III.html]

===Achievements===

They did manage to invent new ways of think about computing. Alan Kay coined the term "object-oriented programming". His inspiration had come from notions of objects already well known in LISP but he wasn't shy about giving credit where it was due. Kay believed his knowledge of LISP helped him think more clearly about computer problems. He felt it contained "great thinking patterns" and "deep beauty" and he vowed to preserve these qualities in the language that would become Smalltalk.

But Kay wasn't just interested the symbolic language at the heart of a system. He incorporated recent studies on learning and cognition from such experts such as Maria Montessori, Jean Piaget, and Jerome Bruner in his goal to form a complete vision of the personal computer. For instance, Bruner's research implied that people learn new thoughts in a loose sequence of translations [http://en.wikipedia.org/wiki/Jerome_Bruner]. First there are actions, or ''enactive'' representations which transform into images or ''iconic'' representations, and finally into language or ''symbolic'' representations. We may take it for granted today, but it was human insights such as these that helped Kay form the basis of graphical user interfaces as channels through which we perceive ideas represented in a computer.

But the language is no small point. The central idea in Smalltalk (and Smalltalk-80 as an example of a whole system) is that "everything is an object". This includes what we already might think of as objects, such as files, forms, and fields but it also includes transformational methods such as actions, behaviors, and calculations. This places it in distinct contrast with operating systems written in C, and even those written in C++. Gone are the notions of ''process'' and ''semaphore''. In their place are ''messages'' between objects and ''events'' to which interested objects may react.

* difference between C and Smalltalk: privacy

(bullet points are future paragraphs)

* adaptation of laser printing to the screen
* after making Smalltalk-80 entirely in Smalltalk, generating Squeak VM in C for performance

===Problems===

* performance issues
* vision mismatch with corporate
* Xerox fumbles the ball
* disillusionment per McLuhan: "our tools reshape us" and "inadequate tools ''still'' reshape us"

===Current Status===

* Continuing Research
* OLPC

==Java Based==
===Overview===

Java is used on a plethora of devices and systems throughout the industry from cell phones to web applets. With Java being a language that creates a virtual machine for each application, one would think that it is already suited to be an operating system in itself but this is not the case. Java is built to run on top of other operating systems such as Microsoft Windows, Mac OS X and Ubuntu Linux rather than being a standalone system. This section will discuss various operating systems that are written in Java such as JavaOS, Android, JNode and JX.

[http://java.sun.com/developer/products/JavaOS/ JavaOS] is Sun Microsystems very own creation. This system runs on different layers to make a scalable and easily updateable operating system [http://java.sun.com/developer/products/JavaOS/OverView/index.html ]. The first layer is the microkernel which handles the memory architecture, booting, interrupt handling, threading, traps and DMA handling. The Java Virtual Machine is also compiled into native code for the system and is run on top of the microkernel. The second layer consists of the JavaOS for Business software which extends the memory module to optimize for systems with limited memory[http://java.sun.com/developer/products/JavaOS/OverView/index.html ]. All device drivers for the system are written and run in Java and are what the third layer is consisted of. Finally, the fourth layer is a stand-alone JDK runtime environment used to run user applications.

[http://www.android.com/ Android] was created by a very ambitious team at Google for use with cell phones. It is basically an operating system running on top of another minimalistic operating system. At the very lowest end of Android, a Linux 2.6 kernel is what powers it. All device drivers are written and compiled for the native hardware or compiled using Google’s Native Development Kit and core system libraries such as libc, OpenGL | ES and SQLite are dynamically linked in per application [http://developer.android.com/guide/basics/what-is-android.html]. In the Android runtime, the Dalvik Virtual Machine (DVM) controls applications similar to the Java Virtual Machine. Dalvik is similar to the aforementioned JavaOS as it relies on the kernel to manage threading and low-level memory management. Running on top of the DVM are core libraries and application frameworks for the Android operating system. These frameworks include resource management, window management, notification manage just to name a few. Applications are then built on top of these frameworks and are the end result in which the user will actually interact with.

[http://www.jnode.org/ JNode] began as the Java Bootable System (JBS) in 1995. Ewout Prangsma, the creator, was unhappy with the amount of native C and assembly used for the system so he began a new project, JNode. JNode only uses a small amount of assembly code for booting the system now compared to the initial JBS [http://www.jnode.org/node/174]. The rest of the system is completely written in Java including its graphical user interface. Applications in JNode are referred to as plugins [http://www.jnode.org/node/175] including the device drivers, filesystems, networking and user applications.

[http://www4.informatik.uni-erlangen.de/Projects/JX/index.html JX] was created at the University of Erlangen. At it’s base is a microkernel that the basic Java Virtual Machine runs on which is similar to JavaOS. The system runs on the idea of domains where the microkernel runs at domain level zero and subsequent programs run in domain A, B, C, etc. Domains contain their own threads, heap and garbage collector and can communicate with other domains using portals. A portal is essentially the same as inter-process communication but using domains as processes instead [http://www.usenix.org/events/usenix02/full_papers/golm/golm.pdf].

===Motivation===

Java is a powerful language that already contains the code necessary for running on many different platforms. With the concept of virtual machines for each individual application it provides a layer of security that not every operating system has. Each virtual machine has it’s own heap which keeps other processes from accessing and writing over already allocated memory since the kernel manages the memory paging. With the use of just-in-time (JIT) compilers, these operating systems can almost achieve comparable run times when compared to native compiled applications.

Since all Java applications are compiled into the same set of bytecode, third-parties can develop their own implementation of the Java runtime. For example, Google has created the Dalvik Virtual Machine for use with the Android platform so it will run more efficiently on small devices while reducing the memory footprint [http://developer.android.com/guide/basics/what-is-android.html]. Google has just recently released Android 2.2 which includes a new JIT compiler for their Dalvik Virtual Machine which can improve speeds of applications up to 2-5 times [http://android-developers.blogspot.com/2010/05/dalvik-jit.html]. IBM also has their own version of the Java Virtual Machine, J9, that is used in many of their own pieces of software and also includes its own implementation of a JIT compiler.

===Achievements===

Android is probably one of the most well-known and mainstream Java based operating system currently on the market. Even though it’s the youngest of the operating systems discussed, it has become one of the newest standards for smartphones. With over 150 devices and counting, Android continues to grow and develop.

===Problems===

One major issue with using Java for an operating system is completely relying on the operating system and kernel to manage memory. Since Java is a garbage collecting language, developers do not have direct access to the memory and have to rely on the operating system to clean up after any objects have been left behind. This can be an issue with lower memory systems while running multiple applications at the same time.

===Current Status===

Each operating system has been created or worked on in the last ten years but some have either halted development or have not seen a major stable release in quite a while. JavaOS is still being maintained by Oracle after they had purchased Sun Microsystems. JNode has not seen an update in over a year and a half [http://sourceforge.net/projects/jnode/files/]. JX also seems to be at a stand still in development with only a minor update after its 0.1 release [http://www4.informatik.uni-erlangen.de/Projects/JX/download-sources.html]. Finally, Android is the most active with minor or major updates coming out every few months. The current state Android is in is Android 2.2 with Android 3.0 currently being hinted for quarter four of 2010 [http://www.techradar.com/news/phone-and-communications/mobile-phones/android-3-0-details-you-need-to-know-706243].

== References ==

Moon, David A. "Genera Retrospective." ''1991 International Workshop on Object Orientation in Operating Systems'' (1991): 2-8. Print.

Moon, David A., Thomas F. Knight, John T. Holloway, and Richard D. Greenblatt. "A Lisp Machine." ''ACM SIGIR Forum'' 15.2 (1980): 137-38. Print.

Pleszkun, A. R., and M. J. Thazhuthaveetil. "The Architecture of Lisp Machines." ''Computer'' 20.3 (1987): 35-44. Print.

COMP 3000 Essay 1 2010 Question 4

2010-10-13T15:34:13Z

ScottG: /* References */

=Question=

What "operating systems" have been implemented in the following languages: LISP, Modula-3, Smalltalk, Java? To what extent do these systems match the capabilities of operating systems implemented in C and C++?

=Team Note (to be removed by delivery date)=

Please use the [[Talk:COMP_3000_Essay_1_2010_Question_4|discussion page]] for any planning and comments.

=Answer=

== Introduction ==

Not so long ago people believed the Earth was a flat world at the center of the universe. This essay addresses a more recent falsehood: that all operating systems are written in assembly language and C. It's not surprising that students of computing in this century would genuflect at the academic altars of Kernighan & Ritchie. After all we grew up with our computer worlds already pre-formed into the conceptual continents of Apple OS, UNIX, and Windows. The more historically curious among us are vaguely aware that other island cultures do exist but they represent civilizations defeated in the marketplace. Explorations into these ancient worlds resemble documentaries about archeologists decoding rediscovered languages etched in stone. But scratch the surface of any of our so-called modern operating systems and you'll find echoes of these ancient languages in our own familiar worlds. Ellen Ullman said it best when she wrote, <blockquote>''We build our computer systems like we build our cities: over time, without a plan, on top of ruins.''</blockquote>

In the sections below we present our explorations into a few truly foundational operating systems. We will also see some brand new ones that prove we stand, as one twelfth century scholar put it, [http://en.wikipedia.org/wiki/Standing_on_the_shoulders_of_giants on the shoulders of giants].

The following is a short list of operating systems written partially or completely with the given language. We will go into more detail in the language-specific sections below.

{| class="wikitable" style="text-align:center" border="1"
|+ '''Operating Systems By Language'''
|-
!width="15%"|Language
!width="85%"|OS List
|-
! Lisp
| MIT's Lisp Machines, Genera
|-
! Modula-3
| SPIN OS
|-
! Smalltalk
| Smalltalk-80 on Xerox Alto, Squeak
|-
! Java
| JavaOS, JNode, JX, Android
|}

==Lisp Based==
===Overview===
Lisp is the second oldest programming languages, established in the late 1960's as a list-processing language. It started out being perfect for math but when it came to programming with it, it left a lot to be desired. Since then there have been a number of different versions of it, from the first Lisp – called “pure Lisp” – to Scheme and Common Lisp. Unlike most object-oriented languages which are focused on classes and instances among other things, Lisp was initially focused more on functions, in which functions call other functions, though later versions of Lisp did eventually add in classes and other typical object-oriented features. It was after this that Genera was created, an operating system written entirely in Lisp, and developed from an earlier operating system on MIT's Lisp Machine.

The Lisp Machine project in began in 1974, where Richard Greenblatt and Thomas Knight, programmers at MIT, designed a computer for general use that was designed for a single user, in which the operating system was programmed entirely in Lisp. It was designed to be completely open to the user, so any changes the user wanted to make could be done during run-time. It was also one of the first systems to be programmed in a 32-bit architecture, making it far more versatile than a number of other operating systems at the time. Despite this, however, the first Lisp Machine was quite basic compared to later iterations, namely Genera.

===Motivation===
Genera is an evolution of the initial Lisp Machine operating system, and as such improved upon many of the basic features of the system. Genera was the first object-oriented operating system, making it stand out among the already well-known Lisp Machines, especially given the fact that it isn't a composition of languages like other operating systems – most using the primary language for the operating system and another language, such as assembly, to deal with hardware directly – but written entirely in Lisp – any of five different dialects of the language – including the lowest levels of the operating system that interact with hardware due to its effective lack of a kernel. Not having to deal with a kernel allows Genera to be very powerful and efficient in certain areas, most especially in the most complex applications such as those dealing with intelligent CAD and graphics, though when given very simple, very routine applications or processes it is much less efficient than other operating systems.

===Achievements===
Another primary difference from other operating systems is that Genera is a fully open system like the first Lisp Machines. Having an open system has its positive and negative aspects. Among the foremost positive aspects is that the user is in control and not left to the whims of the operating system as is common in non-open systems – if the user doesn't like how something is happening, they can simply go in and change it from happening that way again – and allows for very quick prototyping, not needing to wait to compile every little change. Also, due to utilizing very lightweight objects and the fact that everything is in a single address space rather than split across multiple spaces greatly increases efficiency, though again mainly in non-simple tasks.

Like operating systems written in C/C++, Genera has multiple inheritance and automatic garbage collection. Unlike C/C++, however, Genera uses object-oriented memory. This gives Genera a very useful feature that many other systems cannot do, which is that, given a memory address, the system is able to provide the start address, size, and the type of object in that memory location, which increases efficiency. Even the way files are accessed is very different from other operating systems, as it uses a generic file access system; in a generic file access system, rather than following a typical structure of keeping the commands needed for local and networked files different, the commands are the same, meaning that the system essentially acts like a file on a system on the other side of the world is a local file.

===Problems===
Not everything is great with an open system, however, as there are definite security concerns: with an open system, the user can change anything, and programs can interact with other programs and change anything, meaning that if a virus were unleashed on a Genera system it could be catastrophic. To counter this problem Genera systems are protected by a very simple method: keeping the physical system itself out of reach of all but authorized users and behind locked doors. To compare to other operating systems, such as those written in C/C++, it is generally less secure because of the open system, though they are both equally at risk when installing software, as both systems are completely open at that specific junction. Genera also has issues with modularity, as it allows for something to be called even when it is not supposed to be able to be called because, as it is an open system, there is nothing really stopping this from happening. Some versions of Genera and Genera applications are also very well-documented and run quite smoothly, but others are poorly documented and run quite slowly as they are built on top of older versions without any real plan beyond adding on an extra feature here or there over and over again.

===Current Status===
Genera and Lisp Machines, while still being used in a select few locations, are not currently being developed, as their time has passed. Their legacy still lives on, however, in the object-oriented operating systems still in use today.

==Modula-3 Based==
===Overview===

An idea came to mind. A question was proposed. Can an operating system have extensibility, safety, and good performance? A group of computer scientists from Washington University took on this question and tried to come up with an answer. That’s how SPIN operating system was created. SPIN is an operating system that blends the user-level with the kernel level. The main feature is that the kernel can be extended using modules that implement interfaces to meet the applications needs to optimise performance and safety. The programming language used is Modula-3, and the reason for using this language is for its type safe properties like interfaces, extension, and its automatic storage management.

===Motivation===

The team had to meet three important features to make this work, a Flexible kernel with safe extensions and a good overall performance. The goal was to create a specialized operating system that can run a range of applications without sacrificing safety or performance. This system would allow the user programs and applications to manipulate and change the system’s interface to load and access the data or memory needed safely and with a good overall performance. This was possible through the type safe extensions of Modula-3.

===Achievements===

* They pulled it off

===Problems===

* Design issues

===Current Status===

* Still under research

==Smalltalk Based==
===Overview===

<blockquote>The best way to predict the future is to invent it. -- Alan Kay</blockquote>

If you are reading this paper on a personal computer, and it has a GUI with overlapping windows, desktop icons, and a mouse pointer then you owe a debt to a group of researchers led by Alan Kay at Xerox's Palo Alto Research Center, or Xerox PARC. Many of those ideas had appeared elsewhere in one form or another, but the first time they came together in a demonstrable and portable form was in the early 1970s at Xerox on a machine called the Alto [http://en.wikipedia.org/wiki/Xerox_Alto]. Their example of a working personal computer was to be the inspiration that launched Apple into the history books.

===Motivation===

Searching for operating systems written in Smalltalk is an exercise in recursion. The Smalltalk OS was written in -- what else -- Smalltalk. But Alan Kay's Learning Research Group (LRG) didn't just set out to write a clever new language that could bootstrap its own environment. Not only were they in California but they had also just survived the 1960s. Their goal was to produce an entirely new learning environment to "amplify human reach and bring new ways of thinking to a faltering civilization that desperately needed it." [http://www.smalltalk.org/smalltalk/TheEarlyHistoryOfSmalltalk_III.html]

===Achievements===

They did manage to invent new ways of think about computing. Alan Kay coined the term "object-oriented programming". His inspiration had come from notions of objects already well known in LISP but he wasn't shy about giving credit where it was due. Kay believed his knowledge of LISP helped him think more clearly about computer problems. He felt it contained "great thinking patterns" and "deep beauty" and he vowed to preserve these qualities in the language that would become Smalltalk.

But Kay wasn't just interested the symbolic language at the heart of a system. He incorporated recent studies on learning and cognition from such experts such as Maria Montessori, Jean Piaget, and Jerome Bruner in his goal to form a complete vision of the personal computer. For instance, Bruner's research implied that people learn new thoughts in a loose sequence of translations [http://en.wikipedia.org/wiki/Jerome_Bruner]. First there are actions, or ''enactive'' representations which transform into images or ''iconic'' representations, and finally into language or ''symbolic'' representations. We may take it for granted today, but it was human insights such as these that helped Kay form the basis of graphical user interfaces as channels through which we perceive ideas represented in a computer.

But the language is no small point. The central idea in Smalltalk (and Smalltalk-80 as an example of a whole system) is that "everything is an object". This includes what we already might think of as objects, such as files, forms, and fields but it also includes transformational methods such as actions, behaviors, and calculations. This places it in distinct contrast with operating systems written in C, and even those written in C++. Gone are the notions of ''process'' and ''semaphore''. In their place are ''messages'' between objects and ''events'' to which interested objects may react.

* difference between C and Smalltalk: privacy

(bullet points are future paragraphs)

* adaptation of laser printing to the screen
* after making Smalltalk-80 entirely in Smalltalk, generating Squeak VM in C for performance

===Problems===

* performance issues
* vision mismatch with corporate
* Xerox fumbles the ball
* disillusionment per McLuhan: "our tools reshape us" and "inadequate tools ''still'' reshape us"

===Current Status===

* Continuing Research
* OLPC

==Java Based==
===Overview===

Java is used on a plethora of devices and systems throughout the industry from cell phones to web applets. With Java being a language that creates a virtual machine for each application, one would think that it is already suited to be an operating system in itself but this is not the case. Java is built to run on top of other operating systems such as Microsoft Windows, Mac OS X and Ubuntu Linux rather than being a standalone system. This section will discuss various operating systems that are written in Java such as JavaOS, Android, JNode and JX.

[http://java.sun.com/developer/products/JavaOS/ JavaOS] is Sun Microsystems very own creation. This system runs on different layers to make a scalable and easily updateable operating system [http://java.sun.com/developer/products/JavaOS/OverView/index.html ]. The first layer is the microkernel which handles the memory architecture, booting, interrupt handling, threading, traps and DMA handling. The Java Virtual Machine is also compiled into native code for the system and is run on top of the microkernel. The second layer consists of the JavaOS for Business software which extends the memory module to optimize for systems with limited memory[http://java.sun.com/developer/products/JavaOS/OverView/index.html ]. All device drivers for the system are written and run in Java and are what the third layer is consisted of. Finally, the fourth layer is a stand-alone JDK runtime environment used to run user applications.

[http://www.android.com/ Android] was created by a very ambitious team at Google for use with cell phones. It is basically an operating system running on top of another minimalistic operating system. At the very lowest end of Android, a Linux 2.6 kernel is what powers it. All device drivers are written and compiled for the native hardware or compiled using Google’s Native Development Kit and core system libraries such as libc, OpenGL | ES and SQLite are dynamically linked in per application [http://developer.android.com/guide/basics/what-is-android.html]. In the Android runtime, the Dalvik Virtual Machine (DVM) controls applications similar to the Java Virtual Machine. Dalvik is similar to the aforementioned JavaOS as it relies on the kernel to manage threading and low-level memory management. Running on top of the DVM are core libraries and application frameworks for the Android operating system. These frameworks include resource management, window management, notification manage just to name a few. Applications are then built on top of these frameworks and are the end result in which the user will actually interact with.

[http://www.jnode.org/ JNode] began as the Java Bootable System (JBS) in 1995. Ewout Prangsma, the creator, was unhappy with the amount of native C and assembly used for the system so he began a new project, JNode. JNode only uses a small amount of assembly code for booting the system now compared to the initial JBS [http://www.jnode.org/node/174]. The rest of the system is completely written in Java including its graphical user interface. Applications in JNode are referred to as plugins [http://www.jnode.org/node/175] including the device drivers, filesystems, networking and user applications.

[http://www4.informatik.uni-erlangen.de/Projects/JX/index.html JX] was created at the University of Erlangen. At it’s base is a microkernel that the basic Java Virtual Machine runs on which is similar to JavaOS. The system runs on the idea of domains where the microkernel runs at domain level zero and subsequent programs run in domain A, B, C, etc. Domains contain their own threads, heap and garbage collector and can communicate with other domains using portals. A portal is essentially the same as inter-process communication but using domains as processes instead [http://www.usenix.org/events/usenix02/full_papers/golm/golm.pdf].

===Motivation===

Java is a powerful language that already contains the code necessary for running on many different platforms. With the concept of virtual machines for each individual application it provides a layer of security that not every operating system has. Each virtual machine has it’s own heap which keeps other processes from accessing and writing over already allocated memory since the kernel manages the memory paging. With the use of just-in-time (JIT) compilers, these operating systems can almost achieve comparable run times when compared to native compiled applications.

Since all Java applications are compiled into the same set of bytecode, third-parties can develop their own implementation of the Java runtime. For example, Google has created the Dalvik Virtual Machine for use with the Android platform so it will run more efficiently on small devices while reducing the memory footprint [http://developer.android.com/guide/basics/what-is-android.html]. Google has just recently released Android 2.2 which includes a new JIT compiler for their Dalvik Virtual Machine which can improve speeds of applications up to 2-5 times [http://android-developers.blogspot.com/2010/05/dalvik-jit.html]. IBM also has their own version of the Java Virtual Machine, J9, that is used in many of their own pieces of software and also includes its own implementation of a JIT compiler.

===Achievements===

Android is probably one of the most well-known and mainstream Java based operating system currently on the market. Even though it’s the youngest of the operating systems discussed, it has become one of the newest standards for smartphones. With over 150 devices and counting, Android continues to grow and develop.

===Problems===

One major issue with using Java for an operating system is completely relying on the operating system and kernel to manage memory. Since Java is a garbage collecting language, developers do not have direct access to the memory and have to rely on the operating system to clean up after any objects have been left behind. This can be an issue with lower memory systems while running multiple applications at the same time.

===Current Status===

Each operating system has been created or worked on in the last ten years but some have either halted development or have not seen a major stable release in quite a while. JavaOS is still being maintained by Oracle after they had purchased Sun Microsystems. JNode has not seen an update in over a year and a half [http://sourceforge.net/projects/jnode/files/]. JX also seems to be at a stand still in development with only a minor update after its 0.1 release [http://www4.informatik.uni-erlangen.de/Projects/JX/download-sources.html]. Finally, Android is the most active with minor or major updates coming out every few months. The current state Android is in is Android 2.2 with Android 3.0 currently being hinted for quarter four of 2010 [http://www.techradar.com/news/phone-and-communications/mobile-phones/android-3-0-details-you-need-to-know-706243].

== References ==

Moon, David A. "Genera Retrospective." ''1991 International Workshop on Object Orientation in Operating Systems'' (1991): 2-8. Print.
Moon, David A., Thomas F. Knight, John T. Holloway, and Richard D. Greenblatt. "A Lisp Machine." ''ACM SIGIR Forum'' 15.2 (1980): 137-38. Print.
Pleszkun, A. R., and M. J. Thazhuthaveetil. "The Architecture of Lisp Machines." ''Computer'' 20.3 (1987): 35-44. Print.

COMP 3000 Essay 1 2010 Question 4

2010-10-13T15:17:38Z

ScottG: /* Lisp Based */

Talk:COMP 3000 Essay 1 2010 Question 4

2010-10-13T02:26:43Z

ScottG: /* Discussion */

== Discussion ==

Got some stuff up, rough copy only. Meant to get more done, but family stuff came up. More to come tomorrow.

--[[User:ScottG|ScottG]] 02:26, 13 October 2010 (UTC)

Right then, I'm on it.

--[[User:Mkugler|Mkugler]] 01:19, 13 October 2010 (UTC)

Hi MK, and welcome to the group. Anil mentioned Oberon just today, which is apparently another OS based on a cousin of modula-3. If you could find a way to extend the Modula-3 section with Oberon, perhaps with your own subsection (Youcef has already started with a SPIN section) that should help us round things up nicely. Note the goal is to compare capabilities with C/C++, so feel free to take a global view for thematic consistency too. I'll be doing a bit more in this respect on the Smalltalk section. As Anil said in lecture today, it should hold together as an essay even without the wiki-ish headings.

--[[User:Jjpwilso|Jjpwilso]] 01:07, 13 October 2010 (UTC)

Hey guys. I'm a bit late to the punch on this as I've been preoccupied with a ton of other stuff. I've read through what you've all done thus far and frankly think it's phenomenal, which brings me to my quandry. I wasn't here when you all laid claim to the various components of the essay and am not entirely certain where my efforts should be directed. I noticed that LISP so far is empty, but that it was claimed by ScottG on the 8th.

Is there anywhere in particular where you would like me to work? I'm committed to spending the better part of the next 48 hours entirely on this, so I can put together anything remaining that's needed. If you guys can't get back to me, I'll just expand on whatever I can find more information on.

--[[User:Mkugler|Mkugler]] 23:16, 12 October 2010 (UTC)

The SPIN work is looking good Youcef. Note: please try to put links to your sources in the text so we can see where your ideas are coming from.

--[[User:Jjpwilso|Jjpwilso]] 20:45, 12 October 2010 (UTC)

Anil gave me another clue into how he was thinking of comparisons between these OSes and C/C++. For Smalltalk at least the central theme mentions nothing about processes. Smalltalk is about objects, methods, and messages rather than the traditional C notion of processes manipulating data. This distinction or something similar to it may be useful when looking at other operating systems we're exploring.

--[[User:Jjpwilso|Jjpwilso]] 20:42, 12 October 2010 (UTC)

I've got some small amount of comparison in mine (haven't posted it, since I'm still trying to compile info on MIT's Lisp Machine, but will likely have most of it up tonight), but I would think it would be easier to perhaps do some small comparisons in the individual sections -- I'll be pointing out some differences in Genera and C++ OS's in OO memory, for example -- and then make some more broad strokes in the conclusion encompassing two or more of our chosen OS's and C/C++.

--[[User:ScottG|ScottG]] 19:19, 12 October 2010 (UTC)

Hi all. I'm gradually posting the sections that I finished so far I'd love to hear your thoughts and comments.

Anil also mentioned an important note on our question, we have to compare these operating systems to the ones developed using C and C++. Are we going to do that in the conclusion section? because so far we are not answering the second half of the question.

As for the Oberon, I just did a quick read in Wiki and it says that its written in oberon programming language. But it says its based on a modified version of Modula-2 and they don't mention modula-3, can we still talk about this OS? I cant really start on that today I have a chemistery midterm tomorrow morning, and tomorrow I'm going to finish the rest of SPIN sections.

--[[User:Ymoussou|Youcef M.]] 19:00, 12 October 2010 (UTC)

Thanks for the link Anil! For the group: I asked Anil a couple of questions after class today, and another OS he had in mind was [http://en.wikipedia.org/wiki/Oberon_(operating_system) Oberon], invented by the creator of Modula-3. I don't know if there's more to find about this than there is about SPIN but I've got my hands full for now.

--[[User:Jjpwilso|Jjpwilso]] 18:29, 12 October 2010 (UTC)

Rather than Squeak I was thinking about Smalltalk-80. Here's a [http://portal.acm.org/citation.cfm?id=273&dl=GUIDE,ACM book on Smalltalk] that's available online in the ACM digital library. Just the preface should tell you everything you need to know. [[User:Soma|Anil]] 03:15, 12 October 2010 (UTC)

Great work on the Java section. I might toss in a bit on the problems section about cross-platform compatibility once I get done with my part.

--[[User:Jjpwilso|Jjpwilso]] 23:57, 10 October 2010 (UTC)

I've posted what I have written so far for the Java section, if anyone has any suggestion/corrections feel free to post them.
EDIT: I've added the other sections of the Java based operating system.

--[[User:Selliot3|Selliot3]] 16:50, 10 October 2010 (UTC)

Re: Motivation. I had Smalltalk in mind when I roughed out the headings and it's pretty much what you suggested. But the headings are only a guideline. If you prefer a different structure for your sections feel free to improvise. As for format I am assuming an essay style.

Re: SPIN. The ACM site has some stuff. You'll need your student card handy to get through the Carleton Library proxy.

Here are a couple of links (you can find a TON more if you search for SPIN at the top of the portal):

[http://portal.acm.org.proxy.library.carleton.ca/citation.cfm?id=380921.380940&coll=ACM&dl=ACM&CFID=108110330&CFTOKEN=12401653 Distributed LTL model-checking in SPIN]

[http://portal.acm.org.proxy.library.carleton.ca/citation.cfm?id=380921.380935&coll=ACM&dl=ACM&CFID=108110330&CFTOKEN=12401653 Using SPIN for feature interaction analysis—a case study]

--[[User:Jjpwilso|Jjpwilso]] 16:25, 10 October 2010 (UTC)

This is all I could find on SPIN

SPIN-An extensible microkernel for application-specific operating system devices [http://www.dtic.mil/cgi-bin/GetTRDoc?Location=U2&doc=GetTRDoc.pdf&AD=ADA293537]

Extensibility, Safety and Performance in the SPIN Operating System [http://cseweb.ucsd.edu/~savage/papers/Sosp95.pdf]

SPIN-Operating System [http://cs-pub.bu.edu/fac/richwest/cs591_w1/notes/spin.pdf]

Lecture 9: SPIN operating system [http://www.youtube.com/watch?v=YE9uztJ_CFg]

--[[User:Ymoussou|Youcef M.]] 16:06, 10 October 2010 (UTC)

What is meant by "Motivation"? Would that be motivation to use the language for an operating system? Also, what format should we be doing this in? I'm pretty much writing in an essay style for the overview to explain all of the operating systems in Java with an introduction and a paragraph for each of the systems. Then, I would fill out a paragraph or two for Motivation, Problems, etc. Does that seem fine?

--[[User:Selliot3|Selliot3]] 15:13, 10 October 2010 (UTC)

Here's a link to the main [http://www-spin.cs.washington.edu/ SPIN website].

--[[User:Jjpwilso|Jjpwilso]] 16:40, 9 October 2010 (UTC)

I'll start right away, but the reference link doesn't work...

--Youcef M. 15:06, 9 October 2010 (UTC)

Welcome, Youcef. It would probably be best if you focused on one operating system for now. Nobody has claimed SPIN yet, the OS in Modula-3. Do you think you could dig into that? There's a good reference below.

--[[User:Jjpwilso|Jjpwilso]] 15:02, 9 October 2010 (UTC)

Hey guys I'm in the group, sorry for not adding something yet. I've been working on a table which has all the operating systems in those languages and comparing them to each other. But it was harder than I thought, I was trying to find where the OS's are similar and where they are different. It got a little bit long and random; I can find a lot of info on one OS but almost none on the other. Do you guys think its worth the trouble to finish it or should just forget about and keep up with you guys?

--Youcef M. 14:41, 9 October 2010 (UTC)

Particular to Squeak: [http://portal.acm.org.proxy.library.carleton.ca/ft_gateway.cfm?id=263754&type=pdf&coll=ACM&dl=ACM&CFID=107940135&CFTOKEN=78771329 Back to the Future - The Story of Squeak, A Practical Smalltalk Written in Itself]

--[[User:Jjpwilso|Jjpwilso]] 13:29, 9 October 2010 (UTC)

From an interview with Alan Kay, founder of Smalltalk, I tracked down a very useful history:
[http://portal.acm.org.proxy.library.carleton.ca/results.cfm?coll=ACM&dl=ACM&CFID=107940135&CFTOKEN=78771329 The Early History of Smalltalk]. There happen to be some important foundational points in here (with references) that relate to other systems as well. For instance he explains how LISP was a vital part of how he came to understand the power of languages. Warning: it's quite long and I don't understand half of it.

--[[User:Jjpwilso|Jjpwilso]] 13:02, 9 October 2010 (UTC)

I'd be fine doing LISP, among throwing out anything good for the other languages I happen to come across.

--[[User:ScottG|ScottG]] 21:27, 8 October 2010 (UTC)

Okay, lets all put down our preferences here and set a reasonable deadline of Saturday at 23:59 for a cutoff. Smalltalk would be my top choice. Of course any contributions to any language will be welcome.

--[[User:Jjpwilso|Jjpwilso]] 16:07, 8 October 2010 (UTC)

I would love to do the Java section. I`ve done quite a bit of development on Android and have also read a complete book on how the Android operating system works. Of course, there are other OS`s to look at but I`m a big fan of Android so I`m always happy to write about it haha.

--[[User:Selliot3|Selliot3]] 15:44, 8 October 2010 (UTC)

I recommend we use the habit of putting more recent comments at the top in case this gets to be a longish list. I've gone ahead and stubbed out a proposed structure. Please comment (thumbs up/down). If we all agree we can start dividing up the parts so we don't do the same work. We're lucky as a team to have such a nicely partitioned essay to write!

--[[User:Jjpwilso|Jjpwilso]] 13:23, 8 October 2010 (UTC)

Genera (LISP) - http://en.wikipedia.org/wiki/Genera_(operating_system) <-- only for a reference for now 
SPIN (Modula) - http://www-spin.cs.washington.edu%2Fexternal%2Foverview.html 
Squeak (SmallTalk) - http://en.wikipedia.org/wiki/Squeak <-- only a reference, says it's a programming language but can be used as an OS 
JavaOS (Java) - http://java.sun.com/developer/products/JavaOS/ 

--[[User:Selliot3|Selliot3]] 00:16, 6 October 2010 (UTC) or Charles

Not a great site, but gives a nice breakdown of the main points of Squeak - http://www.visoracle.com/squeak/overview.html 
And a much longer, more in-depth Squeak page - http://www.cosc.canterbury.ac.nz/wolfgang.kreutzer/cosc205/smalltalk1.html 
A nice breakdown for JavaOS - http://www.operating-system.org/betriebssystem/_english/bs-javaos.htm 
And a very nice PDF for Genera - http://ieeexplore.ieee.org/xpls/abs_all.jsp?arnumber=183015&tag=1 
--[[User:ScottG|ScottG]] 13:08, 6 October 2010 (UTC)

For Java section: [http://developer.android.com/guide/basics/what-is-android.html What is Android] shows the limited role of DVM (Android's JVM). 
--[[User:Jjpwilso|Jjpwilso]] 14:31, 7 October 2010 (UTC)

Talk:COMP 3000 Essay 1 2010 Question 4

2010-10-13T02:26:30Z

ScottG: /* Discussion */

== Discussion ==

Got some stuff up, rough copy only. Meant to get more done, but family stuff came up. More to come tomorrow.
--[[User:ScottG|ScottG]] 02:26, 13 October 2010 (UTC)

Right then, I'm on it.

--[[User:Mkugler|Mkugler]] 01:19, 13 October 2010 (UTC)

Hi MK, and welcome to the group. Anil mentioned Oberon just today, which is apparently another OS based on a cousin of modula-3. If you could find a way to extend the Modula-3 section with Oberon, perhaps with your own subsection (Youcef has already started with a SPIN section) that should help us round things up nicely. Note the goal is to compare capabilities with C/C++, so feel free to take a global view for thematic consistency too. I'll be doing a bit more in this respect on the Smalltalk section. As Anil said in lecture today, it should hold together as an essay even without the wiki-ish headings.

--[[User:Jjpwilso|Jjpwilso]] 01:07, 13 October 2010 (UTC)

Hey guys. I'm a bit late to the punch on this as I've been preoccupied with a ton of other stuff. I've read through what you've all done thus far and frankly think it's phenomenal, which brings me to my quandry. I wasn't here when you all laid claim to the various components of the essay and am not entirely certain where my efforts should be directed. I noticed that LISP so far is empty, but that it was claimed by ScottG on the 8th.

Is there anywhere in particular where you would like me to work? I'm committed to spending the better part of the next 48 hours entirely on this, so I can put together anything remaining that's needed. If you guys can't get back to me, I'll just expand on whatever I can find more information on.

--[[User:Mkugler|Mkugler]] 23:16, 12 October 2010 (UTC)

The SPIN work is looking good Youcef. Note: please try to put links to your sources in the text so we can see where your ideas are coming from.

--[[User:Jjpwilso|Jjpwilso]] 20:45, 12 October 2010 (UTC)

Anil gave me another clue into how he was thinking of comparisons between these OSes and C/C++. For Smalltalk at least the central theme mentions nothing about processes. Smalltalk is about objects, methods, and messages rather than the traditional C notion of processes manipulating data. This distinction or something similar to it may be useful when looking at other operating systems we're exploring.

--[[User:Jjpwilso|Jjpwilso]] 20:42, 12 October 2010 (UTC)

I've got some small amount of comparison in mine (haven't posted it, since I'm still trying to compile info on MIT's Lisp Machine, but will likely have most of it up tonight), but I would think it would be easier to perhaps do some small comparisons in the individual sections -- I'll be pointing out some differences in Genera and C++ OS's in OO memory, for example -- and then make some more broad strokes in the conclusion encompassing two or more of our chosen OS's and C/C++.

--[[User:ScottG|ScottG]] 19:19, 12 October 2010 (UTC)

Hi all. I'm gradually posting the sections that I finished so far I'd love to hear your thoughts and comments.

Anil also mentioned an important note on our question, we have to compare these operating systems to the ones developed using C and C++. Are we going to do that in the conclusion section? because so far we are not answering the second half of the question.

As for the Oberon, I just did a quick read in Wiki and it says that its written in oberon programming language. But it says its based on a modified version of Modula-2 and they don't mention modula-3, can we still talk about this OS? I cant really start on that today I have a chemistery midterm tomorrow morning, and tomorrow I'm going to finish the rest of SPIN sections.

--[[User:Ymoussou|Youcef M.]] 19:00, 12 October 2010 (UTC)

Thanks for the link Anil! For the group: I asked Anil a couple of questions after class today, and another OS he had in mind was [http://en.wikipedia.org/wiki/Oberon_(operating_system) Oberon], invented by the creator of Modula-3. I don't know if there's more to find about this than there is about SPIN but I've got my hands full for now.

--[[User:Jjpwilso|Jjpwilso]] 18:29, 12 October 2010 (UTC)

Rather than Squeak I was thinking about Smalltalk-80. Here's a [http://portal.acm.org/citation.cfm?id=273&dl=GUIDE,ACM book on Smalltalk] that's available online in the ACM digital library. Just the preface should tell you everything you need to know. [[User:Soma|Anil]] 03:15, 12 October 2010 (UTC)

Great work on the Java section. I might toss in a bit on the problems section about cross-platform compatibility once I get done with my part.

--[[User:Jjpwilso|Jjpwilso]] 23:57, 10 October 2010 (UTC)

I've posted what I have written so far for the Java section, if anyone has any suggestion/corrections feel free to post them.
EDIT: I've added the other sections of the Java based operating system.

--[[User:Selliot3|Selliot3]] 16:50, 10 October 2010 (UTC)

Re: Motivation. I had Smalltalk in mind when I roughed out the headings and it's pretty much what you suggested. But the headings are only a guideline. If you prefer a different structure for your sections feel free to improvise. As for format I am assuming an essay style.

Re: SPIN. The ACM site has some stuff. You'll need your student card handy to get through the Carleton Library proxy.

Here are a couple of links (you can find a TON more if you search for SPIN at the top of the portal):

[http://portal.acm.org.proxy.library.carleton.ca/citation.cfm?id=380921.380940&coll=ACM&dl=ACM&CFID=108110330&CFTOKEN=12401653 Distributed LTL model-checking in SPIN]

[http://portal.acm.org.proxy.library.carleton.ca/citation.cfm?id=380921.380935&coll=ACM&dl=ACM&CFID=108110330&CFTOKEN=12401653 Using SPIN for feature interaction analysis—a case study]

--[[User:Jjpwilso|Jjpwilso]] 16:25, 10 October 2010 (UTC)

This is all I could find on SPIN

SPIN-An extensible microkernel for application-specific operating system devices [http://www.dtic.mil/cgi-bin/GetTRDoc?Location=U2&doc=GetTRDoc.pdf&AD=ADA293537]

Extensibility, Safety and Performance in the SPIN Operating System [http://cseweb.ucsd.edu/~savage/papers/Sosp95.pdf]

SPIN-Operating System [http://cs-pub.bu.edu/fac/richwest/cs591_w1/notes/spin.pdf]

Lecture 9: SPIN operating system [http://www.youtube.com/watch?v=YE9uztJ_CFg]

--[[User:Ymoussou|Youcef M.]] 16:06, 10 October 2010 (UTC)

What is meant by "Motivation"? Would that be motivation to use the language for an operating system? Also, what format should we be doing this in? I'm pretty much writing in an essay style for the overview to explain all of the operating systems in Java with an introduction and a paragraph for each of the systems. Then, I would fill out a paragraph or two for Motivation, Problems, etc. Does that seem fine?

--[[User:Selliot3|Selliot3]] 15:13, 10 October 2010 (UTC)

Here's a link to the main [http://www-spin.cs.washington.edu/ SPIN website].

--[[User:Jjpwilso|Jjpwilso]] 16:40, 9 October 2010 (UTC)

I'll start right away, but the reference link doesn't work...

--Youcef M. 15:06, 9 October 2010 (UTC)

Welcome, Youcef. It would probably be best if you focused on one operating system for now. Nobody has claimed SPIN yet, the OS in Modula-3. Do you think you could dig into that? There's a good reference below.

--[[User:Jjpwilso|Jjpwilso]] 15:02, 9 October 2010 (UTC)

Hey guys I'm in the group, sorry for not adding something yet. I've been working on a table which has all the operating systems in those languages and comparing them to each other. But it was harder than I thought, I was trying to find where the OS's are similar and where they are different. It got a little bit long and random; I can find a lot of info on one OS but almost none on the other. Do you guys think its worth the trouble to finish it or should just forget about and keep up with you guys?

--Youcef M. 14:41, 9 October 2010 (UTC)

Particular to Squeak: [http://portal.acm.org.proxy.library.carleton.ca/ft_gateway.cfm?id=263754&type=pdf&coll=ACM&dl=ACM&CFID=107940135&CFTOKEN=78771329 Back to the Future - The Story of Squeak, A Practical Smalltalk Written in Itself]

--[[User:Jjpwilso|Jjpwilso]] 13:29, 9 October 2010 (UTC)

From an interview with Alan Kay, founder of Smalltalk, I tracked down a very useful history:
[http://portal.acm.org.proxy.library.carleton.ca/results.cfm?coll=ACM&dl=ACM&CFID=107940135&CFTOKEN=78771329 The Early History of Smalltalk]. There happen to be some important foundational points in here (with references) that relate to other systems as well. For instance he explains how LISP was a vital part of how he came to understand the power of languages. Warning: it's quite long and I don't understand half of it.

--[[User:Jjpwilso|Jjpwilso]] 13:02, 9 October 2010 (UTC)

I'd be fine doing LISP, among throwing out anything good for the other languages I happen to come across.

--[[User:ScottG|ScottG]] 21:27, 8 October 2010 (UTC)

Okay, lets all put down our preferences here and set a reasonable deadline of Saturday at 23:59 for a cutoff. Smalltalk would be my top choice. Of course any contributions to any language will be welcome.

--[[User:Jjpwilso|Jjpwilso]] 16:07, 8 October 2010 (UTC)

I would love to do the Java section. I`ve done quite a bit of development on Android and have also read a complete book on how the Android operating system works. Of course, there are other OS`s to look at but I`m a big fan of Android so I`m always happy to write about it haha.

--[[User:Selliot3|Selliot3]] 15:44, 8 October 2010 (UTC)

I recommend we use the habit of putting more recent comments at the top in case this gets to be a longish list. I've gone ahead and stubbed out a proposed structure. Please comment (thumbs up/down). If we all agree we can start dividing up the parts so we don't do the same work. We're lucky as a team to have such a nicely partitioned essay to write!

--[[User:Jjpwilso|Jjpwilso]] 13:23, 8 October 2010 (UTC)

Genera (LISP) - http://en.wikipedia.org/wiki/Genera_(operating_system) <-- only for a reference for now 
SPIN (Modula) - http://www-spin.cs.washington.edu%2Fexternal%2Foverview.html 
Squeak (SmallTalk) - http://en.wikipedia.org/wiki/Squeak <-- only a reference, says it's a programming language but can be used as an OS 
JavaOS (Java) - http://java.sun.com/developer/products/JavaOS/ 

--[[User:Selliot3|Selliot3]] 00:16, 6 October 2010 (UTC) or Charles

Not a great site, but gives a nice breakdown of the main points of Squeak - http://www.visoracle.com/squeak/overview.html 
And a much longer, more in-depth Squeak page - http://www.cosc.canterbury.ac.nz/wolfgang.kreutzer/cosc205/smalltalk1.html 
A nice breakdown for JavaOS - http://www.operating-system.org/betriebssystem/_english/bs-javaos.htm 
And a very nice PDF for Genera - http://ieeexplore.ieee.org/xpls/abs_all.jsp?arnumber=183015&tag=1 
--[[User:ScottG|ScottG]] 13:08, 6 October 2010 (UTC)

For Java section: [http://developer.android.com/guide/basics/what-is-android.html What is Android] shows the limited role of DVM (Android's JVM). 
--[[User:Jjpwilso|Jjpwilso]] 14:31, 7 October 2010 (UTC)

COMP 3000 Essay 1 2010 Question 4

2010-10-13T02:24:54Z

ScottG: /* Lisp Based */

=Question=

What "operating systems" have been implemented in the following languages: LISP, Modula-3, Smalltalk, Java? To what extent do these systems match the capabilities of operating systems implemented in C and C++?

=Team Note (to be removed by delivery date)=

Please use the [[Talk:COMP_3000_Essay_1_2010_Question_4|discussion page]] for any planning and comments.

=Answer=

== Introduction ==

Not so long ago people believed the Earth was a flat world at the center of the universe. This essay addresses a more recent falsehood: that all operating systems are written in assembly language and C. It's not surprising that students of computing in this century would genuflect at the academic altars of Kernighan & Ritchie. After all we grew up with our computer worlds already pre-formed into the conceptual continents of Apple OS, UNIX, and Windows. The more historically curious among us are vaguely aware that other island cultures do exist but they represent civilizations defeated in the marketplace. Explorations into these ancient worlds resemble documentaries about archeologists decoding rediscovered languages etched in stone. But scratch the surface of any of our so-called modern operating systems and you'll find echoes of these ancient languages in our own familiar worlds. Ellen Ullman said it best when she wrote, <blockquote>''We build our computer systems like we build our cities: over time, without a plan, on top of ruins.''</blockquote>

In the sections below we present our explorations into a few truly foundational operating systems. We will also see some brand new ones that prove we stand, as one twelfth century scholar put it, [http://en.wikipedia.org/wiki/Standing_on_the_shoulders_of_giants on the shoulders of giants].

The following is a short list of operating systems written partially or completely with the given language. We will go into more detail in the language-specific sections below.

{| class="wikitable" style="text-align:center" border="1"
|+ '''Operating Systems By Language'''
|-
!width="15%"|Language
!width="85%"|OS List
|-
! Lisp
| MIT's Lisp Machines, Genera
|-
! Modula-3
| SPIN OS
|-
! Smalltalk
| Smalltalk-80 on Xerox Alto, Squeak
|-
! Java
| JavaOS, JNode, JX, Android
|}

==Lisp Based==
===Overview===
Lisp is the second oldest programming languages, established in the late 1960's as a list-processing language. It started out being perfect for math but when it came to programming with it, it left a lot to be desired. Since then there have been a number of different versions of it, from the first Lisp – called “pure Lisp” – to Scheme and Common Lisp. Unlike most object-oriented languages which are focused on classes and instances among other things, Lisp was initially focused more on functions, in which functions call other functions, though later versions of Lisp did eventually add in classes and other typical object-oriented features. It was after this that Genera was created, an operating system written entirely in Lisp, and developed from an earlier operating system on MIT's Lisp Machine.

The Lisp Machine project in began in 1974, where Richard Greenblatt and Thomas Knight, programmers at MIT, designed a computer for general use that was designed for a single user, in which the operating system was programmed entirely in Lisp. It was designed to be completely open to the user, so any changes the user wanted to make could be done during run-time. It was also one of the first systems to be programmed in a 32-bit architecture, making it far more versatile than a number of other operating systems at the time. Despite this, however, the first Lisp Machine was quite basic compared to later iterations, namely Genera.

Genera is an evolution of the initial Lisp Machine operating system, and as such improved upon many of the basic features of the system. Genera was the first object-oriented operating system, making it stand out among the already well-known Lisp Machines, especially given the fact that it isn't a composition of languages like other operating systems, but written entirely in Lisp – any of five different dialects of the language – including the lowest levels of the operating system that interact with hardware due to its effective lack of a kernel.
===Motivation===
===Achievements===
===Problems===
===Current Status===

==Modula-3 Based==
===Overview===

An idea came to mind. A question was proposed. Can an operating system have extensibility, safety, and good performance? A group of computer scientists from Washington University took on this question and tried to come up with an answer. That’s how SPIN operating system was created. SPIN is an operating system that blends the user-level with the kernel level. The main feature is that the kernel can be extended using modules that implement interfaces to meet the applications needs to optimise performance and safety. The programming language used is Modula-3, and the reason for using this language is for its type safe properties like interfaces, extension, and its automatic storage management.

===Motivation===

The team had to meet three important features to make this work, a Flexible kernel with safe extensions and a good overall performance. The goal was to create a specialized operating system that can run a range of applications without sacrificing safety or performance. This system would allow the user programs and applications to manipulate and change the system’s interface to load and access the data or memory needed safely and with a good overall performance. This was possible through the type safe extensions of Modula-3.

===Achievements===

* They pulled it off

===Problems===

* Design issues

===Current Status===

* Still under research

==Smalltalk Based==
===Overview===

<blockquote>The best way to predict the future is to invent it. -- Alan Kay</blockquote>

If you are reading this paper on a personal computer, and it has a GUI with overlapping windows, desktop icons, and a mouse pointer then you owe a debt to a group of researchers led by Alan Kay at Xerox's Palo Alto Research Center, or Xerox PARC. Many of those ideas had appeared elsewhere in one form or another, but the first time they came together in a demonstrable and portable form was in the early 1970s at Xerox on a machine called the Alto [http://en.wikipedia.org/wiki/Xerox_Alto]. Their example of a working personal computer was to be the inspiration that launched Apple into the history books.

===Motivation===

Searching for operating systems written in Smalltalk is an exercise in recursion. The Smalltalk OS was written in -- what else -- Smalltalk. But Alan Kay's Learning Research Group (LRG) didn't just set out to write a clever new language that could bootstrap its own environment. Not only were they in California but they had also just survived the 1960s. Their goal was to produce an entirely new learning environment to "amplify human reach and bring new ways of thinking to a faltering civilization that desperately needed it." [http://www.smalltalk.org/smalltalk/TheEarlyHistoryOfSmalltalk_III.html]

===Achievements===

They did manage to invent new ways of think about computing. Alan Kay coined the term "object-oriented programming". His inspiration had come from notions of objects already well known in LISP but he wasn't shy about giving credit where it was due. Kay believed his knowledge of LISP helped him think more clearly about computer problems. He felt it contained "great thinking patterns" and "deep beauty" and he vowed to preserve these qualities in the language that would become Smalltalk.

But Kay wasn't just interested the symbolic language at the heart of a system. He incorporated recent studies on learning and cognition from such experts such as Maria Montessori, Jean Piaget, and Jerome Bruner in his goal to form a complete vision of the personal computer. For instance, Bruner's research implied that people learn new thoughts in a loose sequence of translations [http://en.wikipedia.org/wiki/Jerome_Bruner]. First there are actions, or ''enactive'' representations which transform into images or ''iconic'' representations, and finally into language or ''symbolic'' representations. We may take it for granted today, but it was human insights such as these that helped Kay form the basis of graphical user interfaces as channels through which we perceive ideas represented in a computer.

(bullet points are future paragraphs)

* difference between C and Smalltalk: processes vs. objects
* adaptation of laser printing to the screen
* after making Smalltalk-80 entirely in Smalltalk, generating Squeak VM in C for performance

===Problems===

* performance issues
* vision mismatch with corporate
* Xerox fumbles the ball
* disillusionment per McLuhan: "our tools reshape us" and "inadequate tools ''still'' reshape us"

===Current Status===

* Continuing Research
* OLPC

==Java Based==
===Overview===

Java is used on a plethora of devices and systems throughout the industry from cell phones to web applets. With Java being a language that creates a virtual machine for each application, one would think that it is already suited to be an operating system in itself but this is not the case. Java is built to run on top of other operating systems such as Microsoft Windows, Mac OS X and Ubuntu Linux rather than being a standalone system. This section will discuss various operating systems that are written in Java such as JavaOS, Android, JNode and JX.

[http://java.sun.com/developer/products/JavaOS/ JavaOS] is Sun Microsystems very own creation. This system runs on different layers to make a scalable and easily updateable operating system [http://java.sun.com/developer/products/JavaOS/OverView/index.html ]. The first layer is the microkernel which handles the memory architecture, booting, interrupt handling, threading, traps and DMA handling. The Java Virtual Machine is also compiled into native code for the system and is run on top of the microkernel. The second layer consists of the JavaOS for Business software which extends the memory module to optimize for systems with limited memory[http://java.sun.com/developer/products/JavaOS/OverView/index.html ]. All device drivers for the system are written and run in Java and are what the third layer is consisted of. Finally, the fourth layer is a stand-alone JDK runtime environment used to run user applications.

[http://www.android.com/ Android] was created by a very ambitious team at Google for use with cell phones. It is basically an operating system running on top of another minimalistic operating system. At the very lowest end of Android, a Linux 2.6 kernel is what powers it. All device drivers are written and compiled for the native hardware or compiled using Google’s Native Development Kit and core system libraries such as libc, OpenGL | ES and SQLite are dynamically linked in per application [http://developer.android.com/guide/basics/what-is-android.html]. In the Android runtime, the Dalvik Virtual Machine (DVM) controls applications similar to the Java Virtual Machine. Dalvik is similar to the aforementioned JavaOS as it relies on the kernel to manage threading and low-level memory management. Running on top of the DVM are core libraries and application frameworks for the Android operating system. These frameworks include resource management, window management, notification manage just to name a few. Applications are then built on top of these frameworks and are the end result in which the user will actually interact with.

[http://www.jnode.org/ JNode] began as the Java Bootable System (JBS) in 1995. Ewout Prangsma, the creator, was unhappy with the amount of native C and assembly used for the system so he began a new project, JNode. JNode only uses a small amount of assembly code for booting the system now compared to the initial JBS [http://www.jnode.org/node/174]. The rest of the system is completely written in Java including its graphical user interface. Applications in JNode are referred to as plugins [http://www.jnode.org/node/175] including the device drivers, filesystems, networking and user applications.

[http://www4.informatik.uni-erlangen.de/Projects/JX/index.html JX] was created at the University of Erlangen. At it’s base is a microkernel that the basic Java Virtual Machine runs on which is similar to JavaOS. The system runs on the idea of domains where the microkernel runs at domain level zero and subsequent programs run in domain A, B, C, etc. Domains contain their own threads, heap and garbage collector and can communicate with other domains using portals. A portal is essentially the same as inter-process communication but using domains as processes instead [http://www.usenix.org/events/usenix02/full_papers/golm/golm.pdf].

===Motivation===

Java is a powerful language that already contains the code necessary for running on many different platforms. With the concept of virtual machines for each individual application it provides a layer of security that not every operating system has. Each virtual machine has it’s own heap which keeps other processes from accessing and writing over already allocated memory since the kernel manages the memory paging. With the use of just-in-time (JIT) compilers, these operating systems can almost achieve comparable run times when compared to native compiled applications.

Since all Java applications are compiled into the same set of bytecode, third-parties can develop their own implementation of the Java runtime. For example, Google has created the Dalvik Virtual Machine for use with the Android platform so it will run more efficiently on small devices while reducing the memory footprint [http://developer.android.com/guide/basics/what-is-android.html]. Google has just recently released Android 2.2 which includes a new JIT compiler for their Dalvik Virtual Machine which can improve speeds of applications up to 2-5 times [http://android-developers.blogspot.com/2010/05/dalvik-jit.html]. IBM also has their own version of the Java Virtual Machine, J9, that is used in many of their own pieces of software and also includes its own implementation of a JIT compiler.

===Achievements===

Android is probably one of the most well-known and mainstream Java based operating system currently on the market. Even though it’s the youngest of the operating systems discussed, it has become one of the newest standards for smartphones. With over 150 devices and counting, Android continues to grow and develop.

===Problems===

One major issue with using Java for an operating system is completely relying on the operating system and kernel to manage memory. Since Java is a garbage collecting language, developers do not have direct access to the memory and have to rely on the operating system to clean up after any objects have been left behind. This can be an issue with lower memory systems while running multiple applications at the same time.

===Current Status===

Each operating system has been created or worked on in the last ten years but some have either halted development or have not seen a major stable release in quite a while. JavaOS is still being maintained by Oracle after they had purchased Sun Microsystems. JNode has not seen an update in over a year and a half [http://sourceforge.net/projects/jnode/files/]. JX also seems to be at a stand still in development with only a minor update after its 0.1 release [http://www4.informatik.uni-erlangen.de/Projects/JX/download-sources.html]. Finally, Android is the most active with minor or major updates coming out every few months. The current state Android is in is Android 2.2 with Android 3.0 currently being hinted for quarter four of 2010 [http://www.techradar.com/news/phone-and-communications/mobile-phones/android-3-0-details-you-need-to-know-706243].

== References ==

User:ScottG

2010-10-13T02:00:19Z

ScottG: Created page with "Scott Graham sgraham6@connect.carleton.ca"

Scott Graham

sgraham6@connect.carleton.ca

Talk:COMP 3000 Essay 1 2010 Question 4

2010-10-12T19:19:07Z

ScottG: /* Discussion */

== Discussion ==

I've got some small amount of comparison in mine (haven't posted it, since I'm still trying to compile info on MIT's Lisp Machine, but will likely have most of it up tonight), but I would think it would be easier to perhaps do some small comparisons in the individual sections -- I'll be pointing out some differences in Genera and C++ OS's in OO memory, for example -- and then make some more broad strokes in the conclusion encompassing two or more of our chosen OS's and C/C++.

--[[User:ScottG|ScottG]] 19:19, 12 October 2010 (UTC)

Hi all. I'm gradually posting the sections that I finished so far I'd love to hear your thoughts and comments.

Anil also mentioned an important note on our question, we have to compare these operating systems to the ones developed using C and C++. Are we going to do that in the conclusion section? because so far we are not answering the second half of the question.

As for the Oberon, I just did a quick read in Wiki and it says that its written in oberon programming language. But it says its based on a modified version of Modula-2 and they don't mention modula-3, can we still talk about this OS? I cant really start on that today I have a chemistery midterm tomorrow morning, and tomorrow I'm going to finish the rest of SPIN sections.

--[[User:Ymoussou|Youcef M.]] 19:00, 12 October 2010 (UTC)

Thanks for the link Anil! For the group: I asked Anil a couple of questions after class today, and another OS he had in mind was [http://en.wikipedia.org/wiki/Oberon_(operating_system) Oberon], invented by the creator of Modula-3. I don't know if there's more to find about this than there is about SPIN but I've got my hands full for now.

--[[User:Jjpwilso|Jjpwilso]] 18:29, 12 October 2010 (UTC)

Rather than Squeak I was thinking about Smalltalk-80. Here's a [http://portal.acm.org/citation.cfm?id=273&dl=GUIDE,ACM book on Smalltalk] that's available online in the ACM digital library. Just the preface should tell you everything you need to know. [[User:Soma|Anil]] 03:15, 12 October 2010 (UTC)

Great work on the Java section. I might toss in a bit on the problems section about cross-platform compatibility once I get done with my part.

--[[User:Jjpwilso|Jjpwilso]] 23:57, 10 October 2010 (UTC)

I've posted what I have written so far for the Java section, if anyone has any suggestion/corrections feel free to post them.
EDIT: I've added the other sections of the Java based operating system.

--[[User:Selliot3|Selliot3]] 16:50, 10 October 2010 (UTC)

Re: Motivation. I had Smalltalk in mind when I roughed out the headings and it's pretty much what you suggested. But the headings are only a guideline. If you prefer a different structure for your sections feel free to improvise. As for format I am assuming an essay style.

Re: SPIN. The ACM site has some stuff. You'll need your student card handy to get through the Carleton Library proxy.

Here are a couple of links (you can find a TON more if you search for SPIN at the top of the portal):

[http://portal.acm.org.proxy.library.carleton.ca/citation.cfm?id=380921.380940&coll=ACM&dl=ACM&CFID=108110330&CFTOKEN=12401653 Distributed LTL model-checking in SPIN]

[http://portal.acm.org.proxy.library.carleton.ca/citation.cfm?id=380921.380935&coll=ACM&dl=ACM&CFID=108110330&CFTOKEN=12401653 Using SPIN for feature interaction analysis—a case study]

--[[User:Jjpwilso|Jjpwilso]] 16:25, 10 October 2010 (UTC)

This is all I could find on SPIN

SPIN-An extensible microkernel for application-specific operating system devices [http://www.dtic.mil/cgi-bin/GetTRDoc?Location=U2&doc=GetTRDoc.pdf&AD=ADA293537]

Extensibility, Safety and Performance in the SPIN Operating System [http://cseweb.ucsd.edu/~savage/papers/Sosp95.pdf]

SPIN-Operating System [http://cs-pub.bu.edu/fac/richwest/cs591_w1/notes/spin.pdf]

Lecture 9: SPIN operating system [http://www.youtube.com/watch?v=YE9uztJ_CFg]

--[[User:Ymoussou|Youcef M.]] 16:06, 10 October 2010 (UTC)

What is meant by "Motivation"? Would that be motivation to use the language for an operating system? Also, what format should we be doing this in? I'm pretty much writing in an essay style for the overview to explain all of the operating systems in Java with an introduction and a paragraph for each of the systems. Then, I would fill out a paragraph or two for Motivation, Problems, etc. Does that seem fine?

--[[User:Selliot3|Selliot3]] 15:13, 10 October 2010 (UTC)

Here's a link to the main [http://www-spin.cs.washington.edu/ SPIN website].

--[[User:Jjpwilso|Jjpwilso]] 16:40, 9 October 2010 (UTC)

I'll start right away, but the reference link doesn't work...

--Youcef M. 15:06, 9 October 2010 (UTC)

Welcome, Youcef. It would probably be best if you focused on one operating system for now. Nobody has claimed SPIN yet, the OS in Modula-3. Do you think you could dig into that? There's a good reference below.

--[[User:Jjpwilso|Jjpwilso]] 15:02, 9 October 2010 (UTC)

Hey guys I'm in the group, sorry for not adding something yet. I've been working on a table which has all the operating systems in those languages and comparing them to each other. But it was harder than I thought, I was trying to find where the OS's are similar and where they are different. It got a little bit long and random; I can find a lot of info on one OS but almost none on the other. Do you guys think its worth the trouble to finish it or should just forget about and keep up with you guys?

--Youcef M. 14:41, 9 October 2010 (UTC)

Particular to Squeak: [http://portal.acm.org.proxy.library.carleton.ca/ft_gateway.cfm?id=263754&type=pdf&coll=ACM&dl=ACM&CFID=107940135&CFTOKEN=78771329 Back to the Future - The Story of Squeak, A Practical Smalltalk Written in Itself]

--[[User:Jjpwilso|Jjpwilso]] 13:29, 9 October 2010 (UTC)

From an interview with Alan Kay, founder of Smalltalk, I tracked down a very useful history:
[http://portal.acm.org.proxy.library.carleton.ca/results.cfm?coll=ACM&dl=ACM&CFID=107940135&CFTOKEN=78771329 The Early History of Smalltalk]. There happen to be some important foundational points in here (with references) that relate to other systems as well. For instance he explains how LISP was a vital part of how he came to understand the power of languages. Warning: it's quite long and I don't understand half of it.

--[[User:Jjpwilso|Jjpwilso]] 13:02, 9 October 2010 (UTC)

I'd be fine doing LISP, among throwing out anything good for the other languages I happen to come across.

--[[User:ScottG|ScottG]] 21:27, 8 October 2010 (UTC)

Okay, lets all put down our preferences here and set a reasonable deadline of Saturday at 23:59 for a cutoff. Smalltalk would be my top choice. Of course any contributions to any language will be welcome.

--[[User:Jjpwilso|Jjpwilso]] 16:07, 8 October 2010 (UTC)

I would love to do the Java section. I`ve done quite a bit of development on Android and have also read a complete book on how the Android operating system works. Of course, there are other OS`s to look at but I`m a big fan of Android so I`m always happy to write about it haha.

--[[User:Selliot3|Selliot3]] 15:44, 8 October 2010 (UTC)

I recommend we use the habit of putting more recent comments at the top in case this gets to be a longish list. I've gone ahead and stubbed out a proposed structure. Please comment (thumbs up/down). If we all agree we can start dividing up the parts so we don't do the same work. We're lucky as a team to have such a nicely partitioned essay to write!

--[[User:Jjpwilso|Jjpwilso]] 13:23, 8 October 2010 (UTC)

Genera (LISP) - http://en.wikipedia.org/wiki/Genera_(operating_system) <-- only for a reference for now 
SPIN (Modula) - http://www-spin.cs.washington.edu%2Fexternal%2Foverview.html 
Squeak (SmallTalk) - http://en.wikipedia.org/wiki/Squeak <-- only a reference, says it's a programming language but can be used as an OS 
JavaOS (Java) - http://java.sun.com/developer/products/JavaOS/ 

--[[User:Selliot3|Selliot3]] 00:16, 6 October 2010 (UTC) or Charles

Not a great site, but gives a nice breakdown of the main points of Squeak - http://www.visoracle.com/squeak/overview.html 
And a much longer, more in-depth Squeak page - http://www.cosc.canterbury.ac.nz/wolfgang.kreutzer/cosc205/smalltalk1.html 
A nice breakdown for JavaOS - http://www.operating-system.org/betriebssystem/_english/bs-javaos.htm 
And a very nice PDF for Genera - http://ieeexplore.ieee.org/xpls/abs_all.jsp?arnumber=183015&tag=1 
--[[User:ScottG|ScottG]] 13:08, 6 October 2010 (UTC)

For Java section: [http://developer.android.com/guide/basics/what-is-android.html What is Android] shows the limited role of DVM (Android's JVM). 
--[[User:Jjpwilso|Jjpwilso]] 14:31, 7 October 2010 (UTC)

Talk:COMP 3000 Essay 1 2010 Question 4

2010-10-08T21:27:36Z

ScottG: /* Discussion */

== Discussion ==

I'd be fine doing LISP, among throwing out anything good for the other languages I happen to come across.

--[[User:ScottG|ScottG]] 21:27, 8 October 2010 (UTC)

Okay, lets all put down our preferences here and set a reasonable deadline of Saturday at 23:59 for a cutoff. Smalltalk would be my top choice. Of course any contributions to any language will be welcome.

--[[User:Jjpwilso|Jjpwilso]] 16:07, 8 October 2010 (UTC)

I would love to do the Java section. I`ve done quite a bit of development on Android and have also read a complete book on how the Android operating system works. Of course, there are other OS`s to look at but I`m a big fan of Android so I`m always happy to write about it haha.

--[[User:Selliot3|Selliot3]] 15:44, 8 October 2010 (UTC)

I recommend we use the habit of putting more recent comments at the top in case this gets to be a longish list. I've gone ahead and stubbed out a proposed structure. Please comment (thumbs up/down). If we all agree we can start dividing up the parts so we don't do the same work. We're lucky as a team to have such a nicely partitioned essay to write!

--[[User:Jjpwilso|Jjpwilso]] 13:23, 8 October 2010 (UTC)

Genera (LISP) - http://en.wikipedia.org/wiki/Genera_(operating_system) <-- only for a reference for now 
SPIN (Modula) - http://www-spin.cs.washington.edu%2Fexternal%2Foverview.html 
Squeak (SmallTalk) - http://en.wikipedia.org/wiki/Squeak <-- only a reference, says it's a programming language but can be used as an OS 
JavaOS (Java) - http://java.sun.com/developer/products/JavaOS/ 

--[[User:Selliot3|Selliot3]] 00:16, 6 October 2010 (UTC) or Charles

Not a great site, but gives a nice breakdown of the main points of Squeak - http://www.visoracle.com/squeak/overview.html 
And a much longer, more in-depth Squeak page - http://www.cosc.canterbury.ac.nz/wolfgang.kreutzer/cosc205/smalltalk1.html 
A nice breakdown for JavaOS - http://www.operating-system.org/betriebssystem/_english/bs-javaos.htm 
And a very nice PDF for Genera - http://ieeexplore.ieee.org/xpls/abs_all.jsp?arnumber=183015&tag=1 
--[[User:ScottG|ScottG]] 13:08, 6 October 2010 (UTC)

For Java section: [http://developer.android.com/guide/basics/what-is-android.html What is Android] shows the limited role of DVM (Android's JVM). 
--[[User:Jjpwilso|Jjpwilso]] 14:31, 7 October 2010 (UTC)

Talk:COMP 3000 Essay 1 2010 Question 4

2010-10-08T21:27:17Z

ScottG: /* Discussion */

== Discussion ==

I'd be fine doing LISP, among throwing out anything good for the other languages I happen to come across.
--[[User:ScottG|ScottG]] 21:27, 8 October 2010 (UTC)

Okay, lets all put down our preferences here and set a reasonable deadline of Saturday at 23:59 for a cutoff. Smalltalk would be my top choice. Of course any contributions to any language will be welcome.

--[[User:Jjpwilso|Jjpwilso]] 16:07, 8 October 2010 (UTC)

I would love to do the Java section. I`ve done quite a bit of development on Android and have also read a complete book on how the Android operating system works. Of course, there are other OS`s to look at but I`m a big fan of Android so I`m always happy to write about it haha.

--[[User:Selliot3|Selliot3]] 15:44, 8 October 2010 (UTC)

I recommend we use the habit of putting more recent comments at the top in case this gets to be a longish list. I've gone ahead and stubbed out a proposed structure. Please comment (thumbs up/down). If we all agree we can start dividing up the parts so we don't do the same work. We're lucky as a team to have such a nicely partitioned essay to write!

--[[User:Jjpwilso|Jjpwilso]] 13:23, 8 October 2010 (UTC)

Genera (LISP) - http://en.wikipedia.org/wiki/Genera_(operating_system) <-- only for a reference for now 
SPIN (Modula) - http://www-spin.cs.washington.edu%2Fexternal%2Foverview.html 
Squeak (SmallTalk) - http://en.wikipedia.org/wiki/Squeak <-- only a reference, says it's a programming language but can be used as an OS 
JavaOS (Java) - http://java.sun.com/developer/products/JavaOS/ 

--[[User:Selliot3|Selliot3]] 00:16, 6 October 2010 (UTC) or Charles

Not a great site, but gives a nice breakdown of the main points of Squeak - http://www.visoracle.com/squeak/overview.html 
And a much longer, more in-depth Squeak page - http://www.cosc.canterbury.ac.nz/wolfgang.kreutzer/cosc205/smalltalk1.html 
A nice breakdown for JavaOS - http://www.operating-system.org/betriebssystem/_english/bs-javaos.htm 
And a very nice PDF for Genera - http://ieeexplore.ieee.org/xpls/abs_all.jsp?arnumber=183015&tag=1 
--[[User:ScottG|ScottG]] 13:08, 6 October 2010 (UTC)

For Java section: [http://developer.android.com/guide/basics/what-is-android.html What is Android] shows the limited role of DVM (Android's JVM). 
--[[User:Jjpwilso|Jjpwilso]] 14:31, 7 October 2010 (UTC)

Talk:COMP 3000 Essay 1 2010 Question 4

2010-10-06T13:08:57Z

ScottG: /* Discussion */

== Discussion ==

Genera (LISP) - http://en.wikipedia.org/wiki/Genera_(operating_system) <-- only for a reference for now 
SPIN (Modula) - http://www-spin.cs.washington.edu%2Fexternal%2Foverview.html 
Squeak (SmallTalk) - http://en.wikipedia.org/wiki/Squeak <-- only a reference, says it's a programming language but can be used as an OS 
JavaOS (Java) - http://java.sun.com/developer/products/JavaOS/ 

--[[User:Selliot3|Selliot3]] 00:16, 6 October 2010 (UTC) or Charles

Not a great site, but gives a nice breakdown of the main points of Squeak - http://www.visoracle.com/squeak/overview.html 
And a much longer, more in-depth Squeak page - http://www.cosc.canterbury.ac.nz/wolfgang.kreutzer/cosc205/smalltalk1.html 
A nice breakdown for JavaOS - http://www.operating-system.org/betriebssystem/_english/bs-javaos.htm 
And a very nice PDF for Genera - http://ieeexplore.ieee.org/xpls/abs_all.jsp?arnumber=183015&tag=1 
--[[User:ScottG|ScottG]] 13:08, 6 October 2010 (UTC)