{"id":1041,"date":"2012-08-15T19:31:54","date_gmt":"2012-08-15T18:31:54","guid":{"rendered":"http:\/\/www.andrewj.com\/blog\/?p=1041"},"modified":"2013-01-17T09:56:50","modified_gmt":"2013-01-17T08:56:50","slug":"the-vmware-disk-io-problem-fixed-at-last","status":"publish","type":"post","link":"https:\/\/www.andrewj.com\/blog\/2012\/the-vmware-disk-io-problem-fixed-at-last\/","title":{"rendered":"The VMWare Disk IO Problem &#8211; Fixed At Last"},"content":{"rendered":"<p>Regular readers will know that I&#8217;m a great fan of VMWare desktop virtualisation, but my enthusiasm has for a long time been muted by an odd problem. After shutting down or suspending a VM my laptop was thrashing its disks for 5-10 minutes, for no apparent reason, making the system almost unusable in the interim. I&#8217;d tried all sorts of variations on disk arrangements but to no avail.<\/p>\n<p>Finally today in desperation I tried googling, which hadn&#8217;t worked previously, and I lucked on the solution. The following site wasn&#8217;t the first reference I found, but it probably offers the best explanation:<br \/>\n<a href=\"http:\/\/olafd.wordpress.com\/2010\/12\/12\/heavy-disk-io-after-shutdown-in-vmware-workstation\/\" target=\"new\">http:\/\/olafd.wordpress.com\/2010\/12\/12\/heavy-disk-io-after-shutdown-in-vmware-workstation\/<\/a><\/p>\n<p>The solution seems to be to simply add the following to each vmx file:<br \/>\n<code>mainMem.useNamedFile = \"false\"<\/code><\/p>\n<p>The difference is little short of miraculous. Not only has the disk IO problem vanished, but I can now attempt operations such as starting or shutting down two VMs simultaneously, which would previously have rendered the system completely unusable, or even crashed it.<\/p>\n<p>It&#8217;s early days, but so far the only downside seems to be that the visible time to suspend or resume a VM has gone up from a couple of seconds to about 15, but that&#8217;s a tiny price to pay.<\/p>\n<p>What annoys me is that if this fix is known, and its effect so dramatic (even if not for every user), then why don&#8217;t VMWare make it more visible on their own sites, and provide it as an option in the WorkStation UI?<\/p>\n<h3>Addendum<\/h3>\n<p>Interesting little &#8220;gotcha&#8221; on this, recently uncovered. If you have a VM with a lot of RAM, and\/or your working files are on a slow disk it can take some time for saved state to write completely to disk <em>after<\/em> VMWare says that saving is complete. If you power the host down while this is happening you will corrupt the saved state and have to completely reboot the VM. I assume that if you wait for the disk to quiesce before powering down the host then things will be OK. Just be careful out there!<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Regular readers will know that I&#8217;m a great fan of VMWare desktop virtualisation, but my enthusiasm has for a long time been muted by an odd problem. After shutting down or suspending a VM my laptop was thrashing its disks &hellip; <a href=\"https:\/\/www.andrewj.com\/blog\/2012\/the-vmware-disk-io-problem-fixed-at-last\/\">Continue reading <span class=\"meta-nav\">&rarr;<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[48],"tags":[],"_links":{"self":[{"href":"https:\/\/www.andrewj.com\/blog\/wp-json\/wp\/v2\/posts\/1041"}],"collection":[{"href":"https:\/\/www.andrewj.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.andrewj.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.andrewj.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.andrewj.com\/blog\/wp-json\/wp\/v2\/comments?post=1041"}],"version-history":[{"count":4,"href":"https:\/\/www.andrewj.com\/blog\/wp-json\/wp\/v2\/posts\/1041\/revisions"}],"predecessor-version":[{"id":1191,"href":"https:\/\/www.andrewj.com\/blog\/wp-json\/wp\/v2\/posts\/1041\/revisions\/1191"}],"wp:attachment":[{"href":"https:\/\/www.andrewj.com\/blog\/wp-json\/wp\/v2\/media?parent=1041"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.andrewj.com\/blog\/wp-json\/wp\/v2\/categories?post=1041"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.andrewj.com\/blog\/wp-json\/wp\/v2\/tags?post=1041"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}