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<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Century Gothic","sans-serif";color:blue">We only have about 200 VMs, but we’ve run into this bug [1] because we use a high number of direct attach luns on our VMs. It takes about 5 minutes to
scan all the fibre channel luns (same issues exists with iSCSI) and used times out before completing (until we changed the value of vdsTimeout higher).<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Century Gothic","sans-serif";color:blue"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Century Gothic","sans-serif";color:blue">Also because of the way our FC storage is presented, we have about 1,400 multipath devices presented to each host. This contributes to really long scan
times and I think causes some general slowness in administration side and “Bad Request” 500 Errors when running some storage commands from the API. VMs themselves still run just fine with no noticeable performance issues though.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Century Gothic","sans-serif";color:blue"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Century Gothic","sans-serif";color:blue">[1]
<a href="https://bugzilla.redhat.com/show_bug.cgi?id=1217401">https://bugzilla.redhat.com/show_bug.cgi?id=1217401</a><o:p></o:p></span></p>
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<p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif"">From:</span></b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif""> Patrick Russell [mailto:patrick_russell@volusion.com]
<br>
<b>Sent:</b> Tuesday, August 18, 2015 3:07 PM<br>
<b>To:</b> Matthew Lagoe<br>
<b>Cc:</b> Groten, Ryan; users@ovirt.org<br>
<b>Subject:</b> Re: [ovirt-users] Benefits of Cluster separation<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Can I ask at what scale you’re running into issues? We’ve got about 500 VM’s running now in a single cluster.
<o:p></o:p></p>
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<p class="MsoNormal">-Patrick<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">On Aug 18, 2015, at 4:03 PM, Matthew Lagoe <<a href="mailto:matthew.lagoe@subrigo.net">matthew.lagoe@subrigo.net</a>> wrote:<o:p></o:p></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">You can have different cluster policy’s at least, don’t know what other benefits there are however as I haven’t noticed any.</span><o:p></o:p></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"> </span><o:p></o:p></p>
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<p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif"">From:</span></b><span class="apple-converted-space"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif""> </span></span><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif""><a href="mailto:users-bounces@ovirt.org"><span style="color:purple">users-bounces@ovirt.org</span></a><span class="apple-converted-space"> </span>[<a href="mailto:users-bounces@ovirt.org"><span style="color:purple">mailto:users-bounces@ovirt.org</span></a>]<span class="apple-converted-space"> </span><b>On
Behalf Of<span class="apple-converted-space"> </span></b>Groten, Ryan<br>
<b>Sent:</b><span class="apple-converted-space"> </span>Tuesday, August 18, 2015 01:59 PM<br>
<b>To:</b><span class="apple-converted-space"> </span><a href="mailto:users@ovirt.org"><span style="color:purple">users@ovirt.org</span></a><br>
<b>Subject:</b><span class="apple-converted-space"> </span>[ovirt-users] Benefits of Cluster separation</span><o:p></o:p></p>
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<p class="MsoNormal"> <o:p></o:p></p>
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<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Century Gothic","sans-serif"">We’re running into some performance problems stemming from having too many Hosts/VMs/Disks running from the same Datacenter/Cluster. Because of that I’m looking into
splitting the DC into multiple separate ones with different Hosts/Storage.</span><o:p></o:p></p>
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<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Century Gothic","sans-serif"">But I’m a little confused what the benefit of separating hosts into clusters achieves. Can someone please explain what the common use cases are? Since all the clusters
in a DC seem to need to see the same storage, I don’t think it would help my situation anyway.</span><o:p></o:p></p>
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<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Century Gothic","sans-serif""> </span><o:p></o:p></p>
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<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Century Gothic","sans-serif"">Thanks,</span><o:p></o:p></p>
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<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Century Gothic","sans-serif"">Ryan<span class="apple-converted-space"> </span></span><o:p></o:p></p>
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<p class="MsoNormal"><span style="font-size:9.0pt;font-family:"Helvetica","sans-serif"">_______________________________________________<br>
Users mailing list<br>
</span><a href="mailto:Users@ovirt.org"><span style="font-size:9.0pt;font-family:"Helvetica","sans-serif";color:purple">Users@ovirt.org</span></a><span style="font-size:9.0pt;font-family:"Helvetica","sans-serif""><br>
</span><a href="http://lists.ovirt.org/mailman/listinfo/users"><span style="font-size:9.0pt;font-family:"Helvetica","sans-serif";color:purple">http://lists.ovirt.org/mailman/listinfo/users</span></a><o:p></o:p></p>
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