{"id":14907,"date":"2013-06-14T13:00:00","date_gmt":"2013-06-14T12:00:00","guid":{"rendered":"https:\/\/aidanfinn.com\/?p=14907"},"modified":"2013-06-14T13:00:00","modified_gmt":"2013-06-14T12:00:00","slug":"windows-server-2012-r2-hyper-v-live-migration-improvements-compression-and-smb-3-0","status":"publish","type":"post","link":"https:\/\/aidanfinn.com\/?p=14907","title":{"rendered":"Windows Server 2012 R2 Hyper-V \u2013 Live Migration Improvements (Compression and SMB 3.0)"},"content":{"rendered":"<p>Live Migration is pretty quick in WS2012 Hyper-V, with support for huge bandwidth with no arbitrary hard limit on the number of concurrent Live Migrations.\u00a0 With the potential for huge hosts (4 TB RAM) and huge VMs (1 TB), Microsoft wanted to make it quicker to move VMs, vacate hosts, and to do general maintenance, such as Cluster Aware Updating.\u00a0 That\u2019s why they added support for faster Live Migration using SMB 3.0 and compression in WS2012 R2 Hyper-V.<\/p>\n<p>Out of the box, WS2012 R2 Hyper-V is able to compress Live Migration traffic.\u00a0 It does this by taking any free CPU resources that are available on the host \u2013 typically CPU is underutilized on hosts.\u00a0 Hyper-V will prioritize other tasks when scheduling the processor.\u00a0 That means if a VM needs more CPU, then Live Migration compression will get less processor access and not impact production systems.\u00a0 Compression is enabled by default and does not require any special hardware.\u00a0 It is expected that Live Migration compression will halve the time it takes to move a VM.<\/p>\n<p><a href=\"https:\/\/aidanfinn.com\/wp-content\/uploads\/2013\/06\/image7.png\"><img loading=\"lazy\" decoding=\"async\" style=\"background-image: none; padding-top: 0px; padding-left: 0px; display: inline; padding-right: 0px; border-width: 0px;\" title=\"image\" src=\"https:\/\/aidanfinn.com\/wp-content\/uploads\/2013\/06\/image_thumb7.png\" border=\"0\" alt=\"image\" width=\"504\" height=\"219\" \/><\/a><\/p>\n<p>If you have access to high end networking then you will want to enable Live Migration over SMB.\u00a0 This will leverage the improvements in SMB from WS2012:<\/p>\n<ul>\n<li>SMB Multichannel: Live Migration will be able to use more than one NIC which means it can get more overall bandwidth.\u00a0 SMB Multichannel automatically discovers new NICs between the SMB client and server and automatically deals with NIC\/path failure.<\/li>\n<li>SMB Direct: This is where you have an RDMA enabled NIC\/network, such as iWARP (10 Gbps), ROCE (10\/40 Gbps), or Infiniband (56 Gbps).\u00a0 The flow of traffic is faster (less latency) and has less impact on the CPU of the SMB client and server.<\/li>\n<\/ul>\n<p><a href=\"https:\/\/aidanfinn.com\/wp-content\/uploads\/2013\/06\/image8.png\"><img loading=\"lazy\" decoding=\"async\" style=\"background-image: none; padding-top: 0px; padding-left: 0px; display: inline; padding-right: 0px; border-width: 0px;\" title=\"image\" src=\"https:\/\/aidanfinn.com\/wp-content\/uploads\/2013\/06\/image_thumb8.png\" border=\"0\" alt=\"image\" width=\"504\" height=\"212\" \/><\/a><\/p>\n<p>On servers with PCI3 slots, 3 of these NICs can give you Live Migration speeds where RAM access speeds become the bottleneck <img decoding=\"async\" class=\"wlEmoticon wlEmoticon-openmouthedsmile\" style=\"border-style: none;\" src=\"https:\/\/aidanfinn.com\/wp-content\/uploads\/2013\/06\/wlEmoticon-openmouthedsmile.png\" alt=\"Open-mouthed smile\" \/><\/p>\n<p>There are\u00a03 scenarios I can think of now, and here are the recommendations from Microsoft for them:<\/p>\n<p><strong><span style=\"text-decoration: underline;\">10 GbE or Slower NIC for Live Migration<\/span><\/strong><\/p>\n<p>Use the default compressed Live Migration.\u00a0 This applies even if you have lots of 1 GbE NICs &#8211; compression will be more effective than SMB 3.0 at these speeds.<\/p>\n<p><strong><span style=\"text-decoration: underline;\">2 or More 10 GbE NICs for Live Migration<\/span><\/strong><\/p>\n<p>Use SMB Live Migration.\u00a0 This will leverage SMB Multichannel to span all of the Live Migration NICs.\u00a0 But watch that CPU utilization on the host.\u00a0 And that leads us to \u2026<\/p>\n<p><strong><span style=\"text-decoration: underline;\">1 or More RDMA NICs for Live Migration<\/span><\/strong><\/p>\n<p>Use SMB Live Migration.\u00a0 This will leverage SMB Direct for really fast Live Migration with low CPU utilization (RDMA offloads processing to the NIC).\u00a0 And if you have more than one NIC you get the best of both worlds by also leveraging SMB Multichannel.<\/p>\n<p>Long story short: Live Migration will be <em>very<\/em> fast on WS2012 R2 Hyper-V, and you\u2019ll see those improvements even on typical 1 GbE networking.<\/p>\n<div id=\"scid:0767317B-992E-4b12-91E0-4F059A8CECA8:dbfbd633-5952-4172-b42c-0bf120d56a59\" class=\"wlWriterSmartContent\" style=\"float: none; margin: 0px; display: inline; padding: 0px;\">Technorati Tags: <a rel=\"tag\" href=\"http:\/\/technorati.com\/tags\/Hyper-V\">Hyper-V<\/a>,<a rel=\"tag\" href=\"http:\/\/technorati.com\/tags\/Windows+Server+2012+R2\">Windows Server 2012 R2<\/a>,<a rel=\"tag\" href=\"http:\/\/technorati.com\/tags\/Virtualisation\">Virtualisation<\/a><\/div>\n","protected":false},"excerpt":{"rendered":"<p>Live Migration is pretty quick in WS2012 Hyper-V, with support for huge bandwidth with no arbitrary hard limit on the number of concurrent Live Migrations.\u00a0 With the potential for huge hosts (4 TB RAM) and huge VMs (1 TB), Microsoft wanted to make it quicker to move VMs, vacate hosts, and to do general maintenance, &hellip; <a href=\"https:\/\/aidanfinn.com\/?p=14907\" class=\"more-link\">Continue reading<span class=\"screen-reader-text\"> &#8220;Windows Server 2012 R2 Hyper-V \u2013 Live Migration Improvements (Compression and SMB 3.0)&#8221;<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"closed","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":[181,195,120],"class_list":["post-14907","post","type-post","status-publish","format-standard","hentry","category-hyper-v","tag-hyper-v","tag-virtualisation","tag-windows-server-2012-r2"],"aioseo_notices":[],"jetpack_featured_media_url":"","amp_enabled":true,"_links":{"self":[{"href":"https:\/\/aidanfinn.com\/index.php?rest_route=\/wp\/v2\/posts\/14907","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=14907"}],"version-history":[{"count":0,"href":"https:\/\/aidanfinn.com\/index.php?rest_route=\/wp\/v2\/posts\/14907\/revisions"}],"wp:attachment":[{"href":"https:\/\/aidanfinn.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=14907"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/aidanfinn.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=14907"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/aidanfinn.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=14907"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}