{"id":2194,"date":"2011-09-09T17:34:17","date_gmt":"2011-09-09T15:34:17","guid":{"rendered":"http:\/\/glandium.org\/blog\/?p=2194"},"modified":"2011-09-10T08:08:41","modified_gmt":"2011-09-10T06:08:41","slug":"initial-vmfs-5-support","status":"publish","type":"post","link":"https:\/\/glandium.org\/blog\/?p=2194","title":{"rendered":"Initial VMFS 5 support"},"content":{"rendered":"<p>Today I added an initial VMFS 5 support to <a href=\"http:\/\/glandium.org\/projects\/vmfs-tools\/\">vmfs-tools<\/a>. For the most part, VMFS 5 is VMFS 3, so these should just work as before, and <a href=\"http:\/\/blogs.vmware.com\/vsphere\/2011\/07\/new-vsphere-50-storage-features-part-1-vmfs-5.html\">adds new features<\/a>; but this initial support is very limited:<\/p>\n<ul>\n<li><b>Unified 1MB File Block Size<\/b> - Nothing has been changed here, so file size is still limited to 256 GB with 1MB File Block Size.<\/li>\n<li><b>Large Single Extent Volumes<\/b> - This is not supported yet. So the 2TB extent limitation still exists.<\/li>\n<li><b>Smaller Sub-Block<\/b> - This actually doesn't change anything to the on-disk format, but is only really the tuning of an existing value in the format. This should be handled out of the box by vmfs-tools.<\/li>\n<li><b>Small File Support<\/b> - VMFS 5 now stores files smaller than 1KB in the inode itself instead of allocating a Sub-Block. Support for this has been added on master.<\/li>\n<li><b>Increased File Count<\/b> - Like smaller Sub-Blocks, this was supported by the on-disk format, and the change is only about tuning, so this should just work out of the box.<\/li>\n<\/ul>\n<p>On related news, while the <a href=\"http:\/\/git.glandium.org\/?p=vmfs-tools.git\">git repository here<\/a> is kept alive, I also pushed it to <a href=\"https:\/\/github.com\/glandium\/vmfs-tools\">github<\/a>. The main reason I did so is the Issue tracker.<\/p>\n<p><b>Update<\/b>: It turns out the small file support makes the vmfs-tools crash when accessing files bigger than 256GB, because the assumption made when reverse engineering was wrong and clashes with how files bigger than 256GB are implemented. It also turns out large single extent volumes may be working already because it looks like it was only about tuning an existing value, like smaller sub-block and increased file count.<\/p>\n<p><b>Update 2<\/b>: Latest master now supports small files without crashing with files bigger than 256GB.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Today I added an initial VMFS 5 support to vmfs-tools. For the most part, VMFS 5 is VMFS 3, so these should just work as before, and adds new features; but this initial support is very limited: Unified 1MB File Block Size &#8211; Nothing has been changed here, so file size is still limited to [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[21],"tags":[23],"class_list":["post-2194","post","type-post","status-publish","format-standard","hentry","category-vmfs-tools","tag-en"],"_links":{"self":[{"href":"https:\/\/glandium.org\/blog\/index.php?rest_route=\/wp\/v2\/posts\/2194","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/glandium.org\/blog\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/glandium.org\/blog\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/glandium.org\/blog\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/glandium.org\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=2194"}],"version-history":[{"count":11,"href":"https:\/\/glandium.org\/blog\/index.php?rest_route=\/wp\/v2\/posts\/2194\/revisions"}],"predecessor-version":[{"id":2221,"href":"https:\/\/glandium.org\/blog\/index.php?rest_route=\/wp\/v2\/posts\/2194\/revisions\/2221"}],"wp:attachment":[{"href":"https:\/\/glandium.org\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=2194"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/glandium.org\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=2194"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/glandium.org\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=2194"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}