https://homeostasis.scs.carleton.ca/wiki/index.php?action=history&feed=atom&title=DistOS_2021F_2021-09-28 2026-05-12T22:49:23Z Revision history for this page on the wiki MediaWiki 1.42.1 https://homeostasis.scs.carleton.ca/wiki/index.php?title=DistOS_2021F_2021-09-28&diff=23354&oldid=prev 2021-09-28T23:36:20Z

<p>Created page with &quot;==Notes== &lt;pre&gt; Lecture 6 --------- Plan 9 - WORM (think CD-R or DVD-R) - optical media that can be written to once and then read many times - hence &quot;jukebox&quot; -...&quot;</p> <p><b>New page</b></p><div>==Notes==<br /> &lt;pre&gt;<br /> Lecture 6<br /> ---------<br /> Plan 9<br /> <br /> - WORM (think CD-R or DVD-R)<br /> - optical media that can be written to once and then read<br /> many times<br /> - hence &quot;jukebox&quot;<br /> - networking &amp; context<br /> - plan 9 is amazing<br /> - how useful is plan 9 to the web?<br /> - I remember before Mosaic, the first popular web browser<br /> - would download files from anonymous ftp sites<br /> - research papers, software, random text files<br /> - send email<br /> - instant messaging on campus<br /> - commercial walled gardens of online content (Compuserve, AOL)<br /> <br /> Plan 9 would have been amazing in the early 1980&#039;s, and maybe could have displaced UNIX. By the late 1980&#039;s and early 1990&#039;s UNIX was too entrenched to easily displace<br /> - breaking backwards compatibility was too much<br /> <br /> For a really cool UNIX workstation, see NeXT<br /> - Plan 9 was never going to take over if it required people to<br /> throw out their existing software<br /> - it was aggressively incompatible with UNIX<br /> - problem wasn&#039;t devices, it was having to port software<br /> - Plan 9&#039;s interfaces were much cleaner, but nobody wants<br /> to port code if they don&#039;t have to<br /> <br /> POSIX is UNIX standards documents<br /> <br /> Plan 9 was very influential<br /> - cool ideas got ported to systems people used, particularly Linux<br /> - UTF-8<br /> - /proc<br /> <br /> Also, how did they do network I/O again?<br /> - TCP or UDP? nope!<br /> - IL/IP (reliable message transport)<br /> - P9 (just a protocol, but what a protocol)<br /> - file server protocol, but...<br /> - in Plan 9 EVERYTHING is a file!<br /> - so lets you share everything!<br /> <br /> UNIX was developed at Bell labs, but TCP/IP wasn&#039;t<br /> - that was built by (D)ARPA-funded folks, particularly<br /> at Berkeley<br /> - they hacked networking into UNIX<br /> - and the UNIX developers didn&#039;t like how they did it<br /> - Plan 9 was their attempt to fix what had been messed up<br /> - and they failed<br /> (they were too late)<br /> <br /> In UNIX, networking uses a different API than files<br /> - but WHY the Plan9 folks say, you could have followed<br /> what we did with UNIX and just made it more files!<br /> - and what is annoying is sockets are kinda file like,<br /> sometimes...<br /> <br /> Evolution wins generally over revolution<br /> - incremental change is just easier<br /> <br /> Could you ssh to a Plan9 system? What sort of interface would you get?<br /> - did Plan 9 support terminals very well? (pure text interfaces)?<br /> <br /> Plan 9 was focused on GUIs in a distributed context<br /> - but we found we wanted text interfaces for our servers!<br /> <br /> Oddly enough the old choices UNIX made to support a variety of text interfaces made it well suited to the web and the cloud<br /> - allowed for easy remote devel and deployment at scale<br /> <br /> Note there isn&#039;t much provision for accessing the Plan 9 systems of other people<br /> <br /> Plan 9 was a solution to old problems, not the new problems that came in the early to mid 90&#039;s with the explosion of the web<br /> - didn&#039;t help build web servers or their database back ends<br /> - and clients were accessing the network with http and a browser,<br /> not 9P<br /> - people didn&#039;t want to share computers, they wanted to share<br /> cute web pages with animated cats<br /> &lt;/pre&gt;</div>

Soma