GATE CS 2020 Set 1 — Question 31

NAT+1 / -0MediumDirect-Mapped CacheMemory Hierarchy & CacheComputer Organization & ArchitectureCache Numericals

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

Last updated 5 September 2026

Question

A direct mapped cache memory of 1 MB has a block size of 256 bytes. The cache has an access time of 3 ns and a hit rate of 94%. During a cache miss, it takes 20 ns to bring the first word of a block from the main memory, while each subsequent word takes 5 ns. The word size is 64 bits. The average memory access time in ns (round off to 1 decimal place) is________.

H

Review answer and solution without JavaScript

Interactive answer checking needs JavaScript. The published solution is available below.

H

Continue learning with Success Tracker

Use Success Tracker to ask about the reasoning, then try another GATE CS question to check your understanding.

AI-powered practice· Unlimited practice on eligible plans

PYQs with solutions: Attempt available previous-year questions, then compare your reasoning with the worked solution. Coverage varies by stream.
Practice that adapts: Choose a topic, work on weaker areas and bookmark questions to revisit. Your attempts feed your progress tracking.
AI doubt support: Ask follow-up questions about a step or concept while practising, instead of stopping at the final answer.

Unlimited practice is available on eligible plans. Free practice and AI usage have limits; check the current plan allowances before choosing.

This page stays readable without an account. AI responses can be wrong; check them against the solution and source material.

2^{32}