{"id":199921,"date":"2025-03-13T04:45:51","date_gmt":"2025-03-13T04:45:51","guid":{"rendered":"https:\/\/learnexams.com\/blog\/?p=199921"},"modified":"2025-03-13T04:45:53","modified_gmt":"2025-03-13T04:45:53","slug":"what-is-the-average-memory-access-time-of-a-machine-whose-hit-rate-is-96-with-a-cache-access-time-of-3-ns-and-a-main-memory-access-time-of-70-ns","status":"publish","type":"post","link":"https:\/\/www.learnexams.com\/blog\/2025\/03\/13\/what-is-the-average-memory-access-time-of-a-machine-whose-hit-rate-is-96-with-a-cache-access-time-of-3-ns-and-a-main-memory-access-time-of-70-ns\/","title":{"rendered":"What is the average memory access time of a machine whose hit rate is 96%, with a cache access time of 3 ns and a main memory access time of 70 ns?"},"content":{"rendered":"\n<p class=\"wp-block-paragraph\">What is the average memory access time of a machine whose hit rate is 96%, with a cache access time of 3 ns and a main memory access time of 70 ns?<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-ast-global-color-6-color\"><strong>The correct answer and explanation is :<\/strong><\/mark><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">To calculate the average memory access time (AMAT) of a system, we consider both cache hits and cache misses. The formula is:<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>AMAT = (Hit Rate \u00d7 Cache Access Time) + (Miss Rate \u00d7 (Cache Access Time + Miss Penalty))<\/strong>\ue206<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Given:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Hit Rate<\/strong> = 96% = 0.96<\/li>\n\n\n\n<li><strong>Cache Access Time<\/strong> = 3 ns<\/li>\n\n\n\n<li><strong>Main Memory Access Time<\/strong> = 70 ns<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">First, calculate the miss rate:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Miss Rate<\/strong> = 1 &#8211; Hit Rate = 1 &#8211; 0.96 = 0.04<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Now, apply the values to the AMAT formula:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>AMAT = (0.96 \u00d7 3 ns) + (0.04 \u00d7 (3 ns + 70 ns))<\/li>\n\n\n\n<li>AMAT = 2.88 ns + (0.04 \u00d7 73 ns)<\/li>\n\n\n\n<li>AMAT = 2.88 ns + 2.92 ns<\/li>\n\n\n\n<li>AMAT = <strong>5.8 ns<\/strong><\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Explanation:<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">In computer systems, the memory hierarchy consists of multiple levels, such as registers, cache, main memory, and secondary storage. Cache memory is a small, high-speed storage located close to the CPU, designed to store copies of frequently accessed data from the main memory. When the CPU needs data, it first checks the cache; if the data is present, it&#8217;s a cache hit, resulting in faster access. If the data isn&#8217;t in the cache, it&#8217;s a cache miss, and the system must access the slower main memory.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The average memory access time provides a metric for the efficiency of the memory system, balancing the speeds of cache and main memory accesses. A higher hit rate improves the AMAT, as more data accesses are serviced quickly by the cache. Conversely, a lower hit rate increases the AMAT due to more frequent accesses to the slower main memory.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">In this scenario, with a 96% hit rate, the system efficiently utilizes the cache, resulting in a low average memory access time of 5.8 ns. This efficiency minimizes delays in data retrieval, enhancing overall system performance.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>What is the average memory access time of a machine whose hit rate is 96%, with a cache access time of 3 ns and a main memory access time of 70 ns? The correct answer and explanation is : To calculate the average memory access time (AMAT) of a system, we consider both cache hits [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"default","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","ast-disable-related-posts":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"footnotes":""},"categories":[25],"tags":[],"class_list":["post-199921","post","type-post","status-publish","format-standard","hentry","category-exams-certification"],"_links":{"self":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/199921","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/comments?post=199921"}],"version-history":[{"count":0,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/199921\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/media?parent=199921"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/categories?post=199921"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/tags?post=199921"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}