<html><head></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; color: rgb(0, 0, 0); font-size: 14px; font-family: Calibri, sans-serif;"><div><div>Does it help if you edit the VM and under Resource Allocation – enable IO threads. ?</div><div><br></div><div>Zip</div><div><span class="Apple-style-span" style="font-size: 12px; font-family: Verdana, Helvetica, Arial;"><br></span></div></div><div><span class="Apple-style-span" style="font-size: 12px; font-family: Verdana, Helvetica, Arial;"><br></span></div><div><span class="Apple-style-span" style="font-size: 12px; font-family: Verdana, Helvetica, Arial;"><br></span></div><span id="OLK_SRC_BODY_SECTION"><div style="font-family:Calibri; font-size:11pt; text-align:left; color:black; BORDER-BOTTOM: medium none; BORDER-LEFT: medium none; PADDING-BOTTOM: 0in; PADDING-LEFT: 0in; PADDING-RIGHT: 0in; BORDER-TOP: #b5c4df 1pt solid; BORDER-RIGHT: medium none; PADDING-TOP: 3pt"><span style="font-weight:bold">From: </span> <<a href="mailto:users-bounces@ovirt.org">users-bounces@ovirt.org</a>> on behalf of Yaniv Kaul <<a href="mailto:ykaul@redhat.com">ykaul@redhat.com</a>><br><span style="font-weight:bold">Date: </span> Saturday, January 20, 2018 at 12:54 PM<br><span style="font-weight:bold">To: </span> Matthias Leopold <<a href="mailto:matthias.leopold@meduniwien.ac.at">matthias.leopold@meduniwien.ac.at</a>><br><span style="font-weight:bold">Cc: </span> Wolfgang Lendl <<a href="mailto:wolfgang.lendl@meduniwien.ac.at">wolfgang.lendl@meduniwien.ac.at</a>>, Ovirt Users <<a href="mailto:users@ovirt.org">users@ovirt.org</a>><br><span style="font-weight:bold">Subject: </span> Re: [ovirt-users] VirtIO-SCSI and viodiskcache custom property<br></div><div><br></div><div><meta http-equiv="Content-Type" content="text/html; charset=utf-8"><div><div dir="auto"><div><br><div class="gmail_extra"><br><div class="gmail_quote">On Jan 19, 2018 3:29 PM, "Matthias Leopold" <<a href="mailto:matthias.leopold@meduniwien.ac.at">matthias.leopold@meduniwien.ac.at</a>> wrote:<br type="attribution"><blockquote class="quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
Hi,<br><br>
is there a reason why the viodiskcache custom property isn't honored when using VirtIO-SCSI?<br><br>
On a Cinder (Ceph) disk "viodiskcache=writeback" is ignored with VirtIO-SCSI and honored when using VirtIO.<br><br>
On an iSCSI disk "viodiskcache=writeback" is ignored with VirtIO-SCSI and the VM can't be started when using VirtIO with "unsupported configuration: native I/O needs either no disk cache or directsync cache mode, QEMU will fallback to aio=threads"<br><br>
We actually want to use "viodiskcache=writeback" with Cinder (Ceph) disks.<br></blockquote></div></div></div><div dir="auto"><br></div><div dir="auto">That's because on block storage we use native io and not threads. I assume the hook needs to change to use native io in this case. </div><div dir="auto">Y. </div><div dir="auto"><br></div><div dir="auto"><div class="gmail_extra"><div class="gmail_quote"><blockquote class="quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><br>
oVirt version: 4.1.8<br><br>
Thanks<br>
Matthias<br><br>
______________________________<wbr>_________________<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<wbr>/listinfo/users</a><br><br><br></blockquote></div><br></div></div></div></div></div></span></body></html>