Free Memory management lessonsMemory management · Stage 1 · Paging · Step 3
The TLB and effective access time
See why paging doubles memory access cost without help, and how a small cache fixes most of it. About 13 minutes.
Memory access takes 100 ns, the TLB lookup 0 ns (assume), and the hit ratio is 90%. What is the effective access time?
- A110 ns
- B100 ns
- C190 ns
Show the answer
110 ns. 0.9 × 100 + 0.1 × 200 = 90 + 20 = 110 ns.
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