On Mon, Jun 8, 2015 at 2:48 PM, Arnaud Virlet <avirlet@xxxxxxxxxxxxxxx> wrote: > Thanks for you reply, > > On 06/08/2015 12:31 PM, Andrey Korolyov wrote: >> >> On Mon, Jun 8, 2015 at 1:24 PM, Arnaud Virlet <avirlet@xxxxxxxxxxxxxxx> >> wrote: >>> >>> Hi >>> >>> Actually we use libvirt VM with ceph rbd pool for storage. >>> By default we want to have "disk cache=writeback" for all disks in >>> libvirt. >>> In /etc/ceph/ceph.conf, we have "rbd cache = true" and for each VMs XML >>> we >>> set "cache=writeback" for all disks in VMs configuration. >>> >>> We want to use one ocfs2 volume on our rbd pool. For this volume we want >>> set >>> cache=none. When we set cache=none in libvirt template for this hosts, it >>> doesn't work. >> >> >> Can you please describe this more specifically? Does the libvirt >> produce a launch string with cache=none or you are measuring the cache >> (mis)presence in some other way? The rbd_cache setting and cache=xxx >> for qemu should show a conjugate behavior. > > > With rbd_cache = true in ceph.conf and cache = none in XML, Libvirt produce > a launch string with cache=none for the ocfs2 volume. Am I understand you right that you are using certain template engine for both OCFS- and RBD-backed volumes within a single VM` config and it does not allow per-disk cache mode separation in a suggested way? > >> >>> The only way that's work is when we set "rbd cache = false" in >>> /etc/ceph/ceph.conf. >>> >>> How can I set cache=none just for one volume specifically without >>> modifing >>> default settings in ceph.conf? >>> >>> >>> Regards, >>> >>> Arnaud >>> _______________________________________________ >>> ceph-users mailing list >>> ceph-users@xxxxxxxxxxxxxx >>> http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com _______________________________________________ ceph-users mailing list ceph-users@xxxxxxxxxxxxxx http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
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