<br><br><div class="gmail_quote"><div dir="ltr">בתאריך יום ה׳, 13 באפר׳ 2017, 16:03, מאת Chris Adams <<a href="mailto:cma@cmadams.net">cma@cmadams.net</a>>:<br></div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">Once upon a time, Yaniv Kaul <<a href="mailto:ykaul@redhat.com" target="_blank">ykaul@redhat.com</a>> said:<br>
> On Tue, Apr 11, 2017 at 3:57 PM, Chris Adams <<a href="mailto:cma@cmadams.net" target="_blank">cma@cmadams.net</a>> wrote:<br>
> > I've been getting an occasional message like:<br>
> ><br>
> > Storage domain hosted_storage experienced a high latency of<br>
> > 5.26121 seconds from host node3.<br>
> ><br>
> > I'm not sure what is causing them though. I look at my storage<br>
> > (EqualLogic iSCSI SAN) and storage network switches and don't see any<br>
> > issues.<br>
> ><br>
> > When the above message was logged, node3 was not hosting the engine<br>
> > (doesn't even have engine HA installed), nor was it the SPM, so why<br>
> > would it have even been accessing the hosted_storage domain?<br>
> ><br>
><br>
> All hosts are monitoring their access to all storage domains in the data<br>
> center.<br>
<br>
Okay. Is there any more information about what this message actually<br>
means though? Is it read latency, write latency, a particular VM, etc.?<br>
<br>
I can't find any issue at the network or SAN level, nor any load events<br>
that correlate with the times oVirt logs the latency messages.<br></blockquote></div><div><br></div><div>Ovirt is reading 4k from the metadata special volume every 10 secods. If the read takes more than 5 seconds, you will see this warning in engine event log.<br></div><div><br></div><div>Maybe your storage or the host was overloaded at that time (e.g. vm backup)?</div><div><br></div><div>Nir</div><div><br></div><div><br></div><div class="gmail_quote"><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"></blockquote></div><div class="gmail_quote"><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
--<br>
Chris Adams <<a href="mailto:cma@cmadams.net" target="_blank">cma@cmadams.net</a>><br>
_______________________________________________<br>
Users mailing list<br>
<a href="mailto:Users@ovirt.org" target="_blank">Users@ovirt.org</a><br>
<a href="http://lists.ovirt.org/mailman/listinfo/users" rel="noreferrer" target="_blank">http://lists.ovirt.org/mailman/listinfo/users</a><br>
</blockquote></div>