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Unformatted text preview: physical page number (PPN) from the page table entry and the VPO from the virtual address. Notice that since the physical and virtual pages are both È bytes, the physical page offset (PPO) is identical to the VPO.
VIRTUAL ADDRESS page table base register (PTBR)
n–1 p p–1 0 virtual page number (VPN) virtual page offset (VPO) valid The VPN acts as index into the page table if valid=0 then page not in memory (page fault) physical page number (PPN) Page Table m–1 p p–1 0 physical page number (PPN) physical page offset (PPO) PHYSICAL ADDRESS Figure 10.13: Address translation with a page table. Figure 10.14(a) shows the steps that the CPU hardware performs when there is a page hit. ¯ ¯ ¯ ¯ ¯ Step 1: The processor generates a virtual address and sends it to the MMU. Step 2: The MMU generates the PTE address and requests it from the cache/main memory. Step 3: The cache/main memory returns the PTE to the MMU. Step 3: The MMU constructs the physical address and sends it to cache/main memory. Step 4: The cache/main memory retur...
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- Spring '10
- The American