Virtual memory allows main memory to act as a cache for secondary storage, using paging to map virtual addresses to physical addresses. This provides efficient and safe memory sharing between programs by allowing them to access memory beyond the limits of RAM. It also eliminates the need for programs to have adjacent memory spaces. Virtual memory improves performance through the use of a translation lookaside buffer (TLB) cache to speed up virtual to physical address translations.

1. Virtual Memory
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● Main memory can act as cache for
secondary memory.
● This is called Virtual Memory.
● Motivation:
○ Efficient and Safe memory share
among programs.
○ Go beyond limited RAM.
○ Not enough adjuscent space.

2. Levels in Memory Hierarchy
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3. A System with Virtual Memory
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4. Terms
Virtual Memory
Page
Page
Fault
Virtual
Address
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5. Virtual Memory
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6. Address Translation via Page Table
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7. Adjuscent Space Not Required
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8. Translation Lookaside Buffer (TLB)
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9. Translation Lookaside Buffer (TLB)
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