{"id":1435,"date":"2020-08-25T22:57:31","date_gmt":"2020-08-26T03:57:31","guid":{"rendered":"https:\/\/notes.technologists.com\/notes\/?p=1435"},"modified":"2020-08-26T14:22:22","modified_gmt":"2020-08-26T19:22:22","slug":"computer-systems-performance-modeling","status":"publish","type":"post","link":"https:\/\/notes.technologists.com\/notes\/2020\/08\/25\/computer-systems-performance-modeling\/","title":{"rendered":"Computer Systems Performance Modeling"},"content":{"rendered":"<p style=\"padding-left: 150px;\">&#8220;Long ago, far away<br \/>\nThings like that don\u2019t happen<br \/>\nNo more, nowadays, do they?&#8221;<br \/>\n(1962) <a href=\"https:\/\/www.bobdylan.com\/songs\/long-ago-far-away\/\" target=\"_blank\" rel=\"noopener noreferrer\">&#8220;Long Ago, Far Away&#8221;<\/a> &#8211; Bob Dylan<\/p>\n<p><a href=\"https:\/\/technologists.com\/sauer\/ComputerSystemsPerformanceModeling.pdf\" target=\"_blank\" rel=\"noopener noreferrer\"><img loading=\"lazy\" decoding=\"async\" data-attachment-id=\"1494\" data-permalink=\"https:\/\/notes.technologists.com\/notes\/2020\/08\/25\/computer-systems-performance-modeling\/cspmcover367x499\/\" data-orig-file=\"https:\/\/notes.technologists.com\/notes\/wp-content\/uploads\/2020\/08\/CSPMcover367x499.jpg\" data-orig-size=\"367,499\" data-comments-opened=\"1\" data-image-meta=\"{&quot;aperture&quot;:&quot;0&quot;,&quot;credit&quot;:&quot;&quot;,&quot;camera&quot;:&quot;&quot;,&quot;caption&quot;:&quot;&quot;,&quot;created_timestamp&quot;:&quot;0&quot;,&quot;copyright&quot;:&quot;&quot;,&quot;focal_length&quot;:&quot;0&quot;,&quot;iso&quot;:&quot;0&quot;,&quot;shutter_speed&quot;:&quot;0&quot;,&quot;title&quot;:&quot;&quot;,&quot;orientation&quot;:&quot;0&quot;}\" data-image-title=\"CSPMcover367x499\" data-image-description=\"\" data-image-caption=\"\" data-large-file=\"https:\/\/notes.technologists.com\/notes\/wp-content\/uploads\/2020\/08\/CSPMcover367x499.jpg\" class=\"alignright wp-image-1494\" src=\"https:\/\/notes.technologists.com\/notes\/wp-content\/uploads\/2020\/08\/CSPMcover367x499-221x300.jpg\" alt=\"\" width=\"147\" height=\"200\" srcset=\"https:\/\/notes.technologists.com\/notes\/wp-content\/uploads\/2020\/08\/CSPMcover367x499-221x300.jpg 221w, https:\/\/notes.technologists.com\/notes\/wp-content\/uploads\/2020\/08\/CSPMcover367x499.jpg 367w\" sizes=\"auto, (max-width: 147px) 100vw, 147px\" \/><\/a><\/p>\n<p><a href=\"https:\/\/technologists.com\/sauer\/ComputerSystemsPerformanceModeling.pdf\" target=\"_blank\" rel=\"noopener noreferrer\">Computer Systems Performance Modeling<\/a>, which Professor <a href=\"https:\/\/www.assemblesoftware.com\/people-k-mani-chandy\" target=\"_blank\" rel=\"noopener noreferrer\">K.M. Chandy<\/a> and I wrote in 1978-9, previously published by Pearson Education, Inc. is now out of print. We are making <a href=\"https:\/\/technologists.com\/sauer\/ComputerSystemsPerformanceModeling.pdf\" target=\"_blank\" rel=\"noopener noreferrer\">PDF<\/a> copies of lightly edited versions available under a Creative Commons license.<\/p>\n<p><!--more--><\/p>\n<p>In the early 1970s, when computing capabilities were tiny, tiny, tiny compared to even a cell phone today, and those resources were typically time-shared across multiple users, queueing network models became a primary tool to analyze and improve system performance. Queueing models had been studied for years before regarding communication systems and other systems, but networks of queues seemed especially <em>apropos<\/em> for understanding time-sharing systems.<\/p>\n<p>There were substantial texts on queueing systems, notably those of Kleinrock and Kobayashi, but in my opinion these emphasized mathematics over modeling. There were numerous books on simulation systems such as GPSS and SIMSCRIPT, but these did not emphasize abstractions to simplify modeling and analysis. There seemed a need for a text designed to facilitate the use of queueing network models in pragmatic ways. Our book was designed to be that text.<span hidden class=\"__iawmlf-post-loop-links\" data-iawmlf-links=\"[{&quot;id&quot;:188,&quot;href&quot;:&quot;https:\\\/\\\/www.bobdylan.com\\\/songs\\\/long-ago-far-away&quot;,&quot;archived_href&quot;:&quot;http:\\\/\\\/web-wp.archive.org\\\/web\\\/20250804200242\\\/https:\\\/\\\/www.bobdylan.com\\\/songs\\\/long-ago-far-away\\\/&quot;,&quot;redirect_href&quot;:&quot;&quot;,&quot;checks&quot;:[{&quot;date&quot;:&quot;2025-11-01 06:39:34&quot;,&quot;http_code&quot;:200},{&quot;date&quot;:&quot;2025-11-08 20:34:05&quot;,&quot;http_code&quot;:200},{&quot;date&quot;:&quot;2025-11-16 13:00:01&quot;,&quot;http_code&quot;:200},{&quot;date&quot;:&quot;2025-11-24 12:58:10&quot;,&quot;http_code&quot;:200},{&quot;date&quot;:&quot;2025-11-27 13:39:54&quot;,&quot;http_code&quot;:200},{&quot;date&quot;:&quot;2025-11-30 16:09:10&quot;,&quot;http_code&quot;:200},{&quot;date&quot;:&quot;2025-12-04 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Chandy and I wrote in 1978-9, previously published by Pearson Education, Inc. is now out of print. We are making PDF copies of lightly edited versions [&hellip;]<\/p>\n","protected":false},"author":3,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":true,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2},"jetpack_post_was_ever_published":false},"categories":[4,7],"tags":[],"class_list":["post-1435","post","type-post","status-publish","format-standard","hentry","category-hardware","category-operating-systems"],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"jetpack_shortlink":"https:\/\/wp.me\/p8c9uP-n9","jetpack-related-posts":[],"_links":{"self":[{"href":"https:\/\/notes.technologists.com\/notes\/wp-json\/wp\/v2\/posts\/1435","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/notes.technologists.com\/notes\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/notes.technologists.com\/notes\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/notes.technologists.com\/notes\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/notes.technologists.com\/notes\/wp-json\/wp\/v2\/comments?post=1435"}],"version-history":[{"count":14,"href":"https:\/\/notes.technologists.com\/notes\/wp-json\/wp\/v2\/posts\/1435\/revisions"}],"predecessor-version":[{"id":1499,"href":"https:\/\/notes.technologists.com\/notes\/wp-json\/wp\/v2\/posts\/1435\/revisions\/1499"}],"wp:attachment":[{"href":"https:\/\/notes.technologists.com\/notes\/wp-json\/wp\/v2\/media?parent=1435"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/notes.technologists.com\/notes\/wp-json\/wp\/v2\/categories?post=1435"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/notes.technologists.com\/notes\/wp-json\/wp\/v2\/tags?post=1435"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}