On 22/10/15 20:01, "Marc Heckmann" <marc.heckmann at ubisoft.com> wrote: >Hi, > >On Thu, 2015-10-22 at 08:17 -0700, Abel Lopez wrote: >> I've actually looked for this for our RBD backed ephemeral instances, >> but found the options lacking. I last looked in Juno. >> >> On Thursday, October 22, 2015, Tim Bell <Tim.Bell at cern.ch> wrote: >> >> >> Has anyone had experience with setting up Nova with KVM so it >> has raw ephemeral disks but qcow2 images for the VMs ? We’ve >> got very large ephemeral disks and could benefit from the >> performance of raw volumes for this. > >We looked into this for the very same reasons and it doesn't seem to be >supported. > >That being said, I'm fearful of the boot time performance impact of >using RAW for ephemeral. > >I suggest you check out the following presentation about qcow2 >performance if you haven't already done so: > >http://events.linuxfoundation.org/sites/events/files/slides/p0.pp_.pdf > >I think it would be worthwhile for Openstack (and libvirt if required) >to support the "l2-cache-size" option for qcow2. +1 for l2-cache-size. This presentation was the basis under which I was looking for a temporary approach until we get the latest qcow2 support. > >-m > >> >> >> >> Tim >> >> >> >> >> _______________________________________________ >> OpenStack-operators mailing list >> OpenStack-operators at lists.openstack.org >> http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-operators > > >_______________________________________________ >OpenStack-operators mailing list >OpenStack-operators at lists.openstack.org >http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-operators