GATE CS 2025 Set 2 — Question 55

NAT+2 / -0MediumCache NumericalsMemory Hierarchy & CacheComputer Organization & Architecture

Computer Organization & Architecture → Memory Hierarchy & Cache → Cache Numericals

Last updated 5 September 2026

Question

Given a computing system with two levels of cache (L1 and L2) and a main memory. The first level (L1) cache access time is 1 nanosecond (ns) and the “hit rate” for L1 cache is 90% while the processor is accessing the data from L1 cache. Whereas, for the second level (L2) cache, the “hit rate” is 80% and the “miss penalty” for transferring data from L2 cache to L1 cache is 10 ns. The “miss penalty” for the data to be transferred from main memory to L2 cache is 100 ns. Then the average memory access time in this system in nanoseconds is___________. (rounded off to one decimal place)

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