{"id":10121,"date":"2009-11-30T20:48:00","date_gmt":"2009-11-30T20:48:00","guid":{"rendered":"https:\/\/aidanfinn.com\/?p=10121"},"modified":"2009-11-30T20:48:00","modified_gmt":"2009-11-30T20:48:00","slug":"live-migrations-are-serial-not-concurrent","status":"publish","type":"post","link":"https:\/\/aidanfinn.com\/?p=10121","title":{"rendered":"Live Migrations Are Serial, Not Concurrent"},"content":{"rendered":"<p>Normally when you move 2 VM\u2019s from one host to another using Live Migration they move one at a time.&#160; Yes, the VMM job pauses at 50% for the second machine for a while \u2013 that\u2019s because it hasn\u2019t started to <a href=\"https:\/\/aidanfinn.com\/?p=10109\" target=\"_blank\">replicate memory<\/a> yet.&#160; The live migrations are serial, not concurrent.&#160; The memory of a running VM is being copied across a network so the network becomes a bottleneck.<\/p>\n<p>I ran a little test across 3 Windows Server 2008 R2 Hyper-V cluster nodes to see what would happen.&#160; I started moving a VM from Host A to Host C.&#160; I also started moving a VM from Host B to host C.&#160; The first one ran straight through.&#160; The second one paused at 50% until the first one was moved \u2013 just like moving 2 VM\u2019s from one host to another.<\/p>\n<div style=\"padding-bottom: 0px; margin: 0px; padding-left: 0px; padding-right: 0px; display: inline; float: none; padding-top: 0px\" id=\"scid:0767317B-992E-4b12-91E0-4F059A8CECA8:25083b88-5bcd-4de6-a8df-8b5c3bdbb1a5\" class=\"wlWriterEditableSmartContent\">Technorati Tags: <a href=\"http:\/\/technorati.com\/tags\/Hyper-V\" rel=\"tag\">Hyper-V<\/a>,<a href=\"http:\/\/technorati.com\/tags\/Windows+Server+2008+R2\" rel=\"tag\">Windows Server 2008 R2<\/a>,<a href=\"http:\/\/technorati.com\/tags\/Live+Migration\" rel=\"tag\">Live Migration<\/a><\/div>\n","protected":false},"excerpt":{"rendered":"<p>Normally when you move 2 VM\u2019s from one host to another using Live Migration they move one at a time.&#160; Yes, the VMM job pauses at 50% for the second machine for a while \u2013 that\u2019s because it hasn\u2019t started to replicate memory yet.&#160; The live migrations are serial, not concurrent.&#160; The memory of a &hellip; <a href=\"https:\/\/aidanfinn.com\/?p=10121\" class=\"more-link\">Continue reading<span class=\"screen-reader-text\"> &#8220;Live Migrations Are Serial, Not Concurrent&#8221;<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"om_disable_all_campaigns":false,"_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"_uf_show_specific_survey":0,"_uf_disable_surveys":false,"footnotes":""},"categories":[20],"tags":[181,74,196,117],"class_list":["post-10121","post","type-post","status-publish","format-standard","hentry","category-hyper-v","tag-hyper-v","tag-live-migration","tag-vmm","tag-windows-server-2008-r2"],"aioseo_notices":[],"jetpack_featured_media_url":"","amp_enabled":true,"_links":{"self":[{"href":"https:\/\/aidanfinn.com\/index.php?rest_route=\/wp\/v2\/posts\/10121","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/aidanfinn.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/aidanfinn.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/aidanfinn.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/aidanfinn.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=10121"}],"version-history":[{"count":0,"href":"https:\/\/aidanfinn.com\/index.php?rest_route=\/wp\/v2\/posts\/10121\/revisions"}],"wp:attachment":[{"href":"https:\/\/aidanfinn.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=10121"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/aidanfinn.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=10121"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/aidanfinn.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=10121"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}