COMP 3000 2011 Week 3 Notes - Revision history

Caesar: /* Xen and the Art of Virtualization */

2011-12-18T20:52:12Z

Xen and the Art of Virtualization

← Older revision		Revision as of 20:52, 18 December 2011
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	'''Emulation vs. Virtualization'''		'''Emulation vs. Virtualization'''

	'''Emulation''': mimicing the original hardware that something ~~run~~ on and how it worked. This is used to run code that is ''not native'' to your processor		'''Emulation''': mimicing the original hardware that something ran on and how it worked. This is used to run code that is ''not native'' to your processor

	'''Virtualization''': running code that you would be able to run regardless as the code is ''native'' to your processor		'''Virtualization''': running code that you would be able to run regardless as the code is ''native'' to your processor

Caesar: /* Xen and the Art of Virtualization */

2011-12-18T20:51:23Z

Xen and the Art of Virtualization

← Older revision		Revision as of 20:51, 18 December 2011
Line 14:		Line 14:
	'''Emulation vs. Virtualization'''		'''Emulation vs. Virtualization'''

	'''Emulation''': mimicing the original hardware that something ~~ran~~ on and how it worked. This is used to run code that is ''not native'' to your processor		'''Emulation''': mimicing the original hardware that something run on and how it worked. This is used to run code that is ''not native'' to your processor

	'''Virtualization''': running code that you would be able to run regardless as the code is ''native'' to your processor		'''Virtualization''': running code that you would be able to run regardless as the code is ''native'' to your processor

	===Definitions===		===Definitions===

Gbooth: Created page with "==Virtualization Basics== ===DLLs=== * For libraries at runtime, library requests are built into the program binary. * ''proc/pid'': structure of process ''proc'' with process …"

2011-10-19T15:28:13Z

Created page with "==Virtualization Basics== ===DLLs=== * For libraries at runtime, library requests are built into the program binary. * ''proc/pid'': structure of process ''proc'' with process …"

New page

==Virtualization Basics==

===DLLs===

* For libraries at runtime, library requests are built into the program binary.
* ''proc/pid'': structure of process ''proc'' with process ID ''pid''
* ''/mmap'': map file into into memory (only load parts of file as the process loads them and don't load multiple copies of the file)
* ''/maps'': what files have been mmapped into a process' address space

===Xen and the Art of Virtualization===

'''Paravirtualization''': an answer to how to run an OS (kernel) as a regular program--this is mainly done by modifying the kernel to strip it of its privileges (another answer to this is to use a hypervisor)

'''Emulation vs. Virtualization'''

'''Emulation''': mimicing the original hardware that something ran on and how it worked. This is used to run code that is ''not native'' to your processor

'''Virtualization''': running code that you would be able to run regardless as the code is ''native'' to your processor

===Definitions===

'''Kernel''': ''part'' of the OS in charge of hardware; the middleman between programs and hardware. The kernel is the first part of the OS that runs, therefore it takes the power and privileges that come with running furst (running in ''supervisor mode''). The kernel is meant to multiplex between applications.

'''Hypervisor''': an OS kernel can be superceded by a hypervisor. The hypervisor runs in ''hypervisor mode'' and is meant for multiplexing between kernels.

'''Concurrency''': when several computations are executing simultaneously, and possibly interacting with each other, in a system. Usually no one wants to deal with the concurrency part of the kernel.

'''Threads vs. Processes'''

'''Thread''': an execution context in an address space. Multiple threads can share the same address space (i.e. be contained in the same process) and can all interact on shared data.

'''Process''': an address space that can contain one or more execution context (i.e. threads). Each process has its own address space.