Uses of VM

Uses of VM - Uses of VM The VM is not only to be able to...

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Uses of VM The VM is not only to be able to run programs that use more memory than the RAM available. VM also speeds up the execution of programs: 1. Mmap the text segment of an executable or shared library 2. Mmap the data segment of a program 3. Use of VM during fork to copy memory of the parent into the child 4. Allocate zero-initialized memory. it is used to allocate space for bss, stack and sbrk() 5. Shared Memory
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1. Mmap the text segment of an executable or a shared library initially mmap does not read any pages any pages will be loaded on demand when they are accessed startup time is fast because only the pages needed will be loaded instead of the entire program It also saves RAM because only the portions of the program that are needed will be in RAM
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executable or a shared library Physical pages where the text segment is stored is shared by multiple instances of the same program. Protections: PROT_READ|PROT_EXEC
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This note was uploaded on 01/30/2012 for the course CS 354 taught by Professor Staff during the Fall '08 term at Purdue.

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Uses of VM - Uses of VM The VM is not only to be able to...

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