Consider a 32-bit machine where four-level paging scheme is used. If the hit…
2011
Consider a 32-bit machine where four-level paging scheme is used. If the hit ratio to TLB is 98%, and it takes 20 nanosecond to search the TLB and 100 nanoseconds to access the main memory what is effective memory access time in nanoseconds?
Answer: B. 128 — Effective Memory Access Time (EMAT) is calculated by weighting hit and miss scenarios. TLB Hit Time = TLB Search + Memory Access = 20 ns + 100 ns = 120 ns.…
- A.
126
- B.
128
- C.
122
- D.
120
Attempted by 211 students.
Show answer & explanation
Correct answer: B
Effective Memory Access Time (EMAT) is calculated by weighting hit and miss scenarios.
TLB Hit Time = TLB Search + Memory Access = 20 ns + 100 ns = 120 ns.
TLB Miss Time = TLB Search + (Page Table Levels * Memory Access) + Final Memory Access = 20 ns + (4 * 100 ns) + 100 ns = 520 ns.
EMAT = (Hit Ratio * Hit Time) + (Miss Ratio * Miss Time)
EMAT = (0.98 * 120) + (0.02 * 520)
EMAT = 117.6 + 10.4 = 128 ns.
A video solution is available for this question — log in and enroll to watch it.
Explore the full course: Iocl Engineers Officers Grade A Paper 2