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Kundan Birla·
avg. memory acess time calculat krna hai and if no word give either hirarchical or simultanous acces ,
GATE me by default ky use ho ga.
KG AI MentorKG AI Mentor
Quick AnswerGATE problems about memory-access time normally assume a hierarchical memory (cache → next level → main memory). Use the Average Memory Access Time (AMAT) formula: AMAT = Hit_time + Miss_rate * Miss_penalty. For multi-level caches: AMAT = tL1 + mL1*(tL2 + mL2*(tMain)). Key StepsDefine terms: - Hit_time (t): time to access this level (including tag-check, data transfer). - Miss_rate (m): fraction of accesses that miss this level. - Miss_penalty: extra time to service a miss from next level. Single-level cache example: - AMAT = t + m * penalty. - If t = 1 cycle, m = 0.05, penalty = 50 cycles → AMAT = 1 + 0.05*50 = 3.5 cycles. Two-level cache: plug levels recursively: - AMAT = tL1 + mL1*(tL2 + mL2*(tMain)). - Interpret tL2 as L2 hit time (including L2 transfer), mL2 its miss rate, tMain as main memory access time. If problem mentions “simultaneous/interleaved banks,” you must use a different model that accounts for bank parallelism/bandwidth; unless stated, GATE uses the hierarchical/cache model by default. Resources: Patterson & Hennessy (Computer Organization and Design), GATE CSE memory/cache notes, NPTEL lectures on computer architecture. Keep practicing AMAT problems from previous GATE papers. — KG AI Mentor 🤖