This is a multi-part message in MIME format. --------------00EFFC74F23A0F6D5A7D770C Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Many thanks for your input Markus. Helps to device before putting the server in production. Regards Fernando On 08/06/2017 02:19, Markus Stockhausen wrote:
Hi Fernando,
we personally like XFS very much. But XFS + qcow2 (even for snapshots in OVirt) comes close to a no-go these days. We are experience excessive fragmentation. For more info see unresolved Redhat Info:
https://access.redhat.com/solutions/532663
Even with tuning the XFS allocation policy on the qcow2 directory with
xfs_io -c 'extsize -R 2M' <qcow2-dir>
A nice 3rd party explanation can be found here:
https://blog.codecentric.de/en/2017/04/xfs-possible-memory-allocation-deadlo...
Markus
------------------------------------------------------------------------ *Von:* users-bounces@ovirt.org [users-bounces@ovirt.org]" im Auftrag von "FERNANDO FREDIANI [fernando.frediani@upx.com] *Gesendet:* Mittwoch, 7. Juni 2017 23:35 *An:* users@ovirt.org *Betreff:* [ovirt-users] Performance differences between ext4 and XFS
Just wanted to find out what filesystem people are using to host Virtual Machines in qcow2 files in a filesystem in Localstorage, ext4 or XFS ?
I normally like XFS for big files which is the case fo VMs, but wondered if anyone could see any performance advantage when compared with ext4.
Fernando
--------------00EFFC74F23A0F6D5A7D770C Content-Type: text/html; charset=windows-1252 Content-Transfer-Encoding: 8bit <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=windows-1252"> </head> <body bgcolor="#FFFFFF" text="#000000"> <p>Many thanks for your input Markus. Helps to device before putting the server in production.</p> <p>Regards<br> Fernando<br> </p> <br> <div class="moz-cite-prefix">On 08/06/2017 02:19, Markus Stockhausen wrote:<br> </div> <blockquote type="cite" cite="mid:12EF8D94C6F8734FB2FF37B9FBEDD173010E01D79F@EXCHANGE.collogia.de"> <meta http-equiv="Content-Type" content="text/html; charset=windows-1252"> <style type="text/css" id="owaParaStyle"></style> <div style="direction: ltr;font-family: Arial;color: #000000;font-size: 10pt;"> <div> <div> <div> <div> <div> <div> <div> <div style="font-family: Tahoma; font-size: 13px;">Hi Fernando, </div> <div style="font-family: Tahoma; font-size: 13px;"><br> </div> <div style="font-family: Tahoma; font-size: 13px;">we personally like XFS very much. But XFS + qcow2 (even for snapshots in OVirt)</div> <div style="font-family: Tahoma; font-size: 13px;">comes close to a no-go these days. We are experience excessive fragmentation.</div> <div style="font-family: Tahoma; font-size: 13px;">For more info see unresolved Redhat Info:</div> <div><font face="Tahoma"><span style="font-size: 13px;"><br> </span></font></div> <div><font face="Tahoma"><span style="font-size: 13px;"><a class="moz-txt-link-freetext" href="https://access.redhat.com/solutions/532663">https://access.redhat.com/solutions/532663</a></span></font></div> <div style="font-family: Tahoma; font-size: 13px;"><br> </div> <div style="font-family: Tahoma; font-size: 13px;">Even with tuning the XFS allocation policy on the qcow2 directory with </div> <div style="font-family: Tahoma; font-size: 13px;"><br> </div> <div><font face="Tahoma"><span style="font-size: 13px;">xfs_io -c 'extsize -R 2M' <qcow2-dir></span></font></div> <div style="font-family: Tahoma; font-size: 13px;"><br> </div> <div style="font-family: Tahoma; font-size: 13px;">A nice 3rd party explanation can be found here:</div> <div style="font-family: Tahoma; font-size: 13px;"><br> </div> <div><font face="Tahoma"><span style="font-size: 13px;"><a class="moz-txt-link-freetext" href="https://blog.codecentric.de/en/2017/04/xfs-possible-memory-allocation-deadlock-kmem_alloc/">https://blog.codecentric.de/en/2017/04/xfs-possible-memory-allocation-deadlock-kmem_alloc/</a></span></font></div> <div style="font-family: Tahoma; font-size: 13px;"><br> </div> <div style="font-family: Tahoma; font-size: 13px;">Markus</div> <div style="font-family: Tahoma; font-size: 13px;"><br> </div> </div> </div> </div> </div> </div> </div> </div> <div style="font-family: Times New Roman; color: #000000; font-size: 16px"> <hr tabindex="-1"> <div id="divRpF447039" style="direction: ltr;"><font color="#000000" face="Tahoma" size="2"><b>Von:</b> <a class="moz-txt-link-abbreviated" href="mailto:users-bounces@ovirt.org">users-bounces@ovirt.org</a> [<a class="moz-txt-link-abbreviated" href="mailto:users-bounces@ovirt.org">users-bounces@ovirt.org</a>]" im Auftrag von "FERNANDO FREDIANI [<a class="moz-txt-link-abbreviated" href="mailto:fernando.frediani@upx.com">fernando.frediani@upx.com</a>]<br> <b>Gesendet:</b> Mittwoch, 7. Juni 2017 23:35<br> <b>An:</b> <a class="moz-txt-link-abbreviated" href="mailto:users@ovirt.org">users@ovirt.org</a><br> <b>Betreff:</b> [ovirt-users] Performance differences between ext4 and XFS<br> </font><br> </div> <div><font face="arial, helvetica, sans-serif">Just wanted to find out what filesystem people are using to host </font>Virtual Machines in qcow2 files in a filesystem in Localstorage, ext4 or XFS ?<br> <br> I normally like XFS for big files which is the case fo VMs, but wondered if anyone could see any performance advantage when compared with ext4.<br> <br> Fernando<br> </div> </div> </div> </blockquote> <br> </body> </html> --------------00EFFC74F23A0F6D5A7D770C--