<table cellspacing="0" cellpadding="0" border="0" ><tr><td valign="top" style="font: inherit;">Hello,<br>The cache settings would also depend on the underlying storage. If you are planning to use something like ext4 partition on the local harddisk then cache=none would be suitable.<br><br>It would be good to avoid cache=writeback on production environment as there no guarantees that the write actually got saved to harddisk.<br><br>cache=writethrough though slower than writeback is the most recommended for the production environments.<br><br>To get better performance it would be good to identify what additional performance can be extracted from the underlying storage subsystem. <br><br><br>Thanks and Regards<br>Saurav Lahiri<br>Hexagrid Computing<br><br><br>--- On <b>Sun, 5/2/12, Stefan G. Weichinger <i><lists@xunil.at></i></b> wrote:<br><blockquote style="border-left: 2px solid rgb(16, 16, 255); margin-left: 5px; padding-left: 5px;"><br>From:
 Stefan G. Weichinger <lists@xunil.at><br>Subject: [libvirt-users] qcow2 performance<br>To: libvirt-users@redhat.com<br>Date: Sunday, 5 February, 2012, 18:31<br><br><div class="plainMail"><br>Greets,<br><br>I have to research performance-issues of a W2003-VM within KVM.<br><br>Right now it's a qcow2-image-file w/ default settings within libvirt<br>(configured by vmm ...)<br><br>My question:<br><br>what caching to use?<br><br>writeback/writethrough/etc  ... what to use for data integrity while not<br>getting ultraslow performance?<br><br>Found<br><br><a href="https://www.linuxfoundation.jp/jp_uploads/JLS2009/jls09_hellwig.pdf" target="_blank">https://www.linuxfoundation.jp/jp_uploads/JLS2009/jls09_hellwig.pdf</a><br><br>Is there any other list/doc what to use and why?<br><br>Thanks, Stefan<br><br>_______________________________________________<br>libvirt-users mailing list<br><a ymailto="mailto:libvirt-users@redhat.com"
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