Hi everyone, I don't think this has been posted to this list before, so just writing it up so it ends up in the archives. tl;dr: Using RBD storage pools with libvirt is currently broken on Ubuntu trusty (LTS), and any other platform using libvirt 1.2.2. In libvirt 1.2.2, the rbd_create3 function is invoked, on volume creation from a pool, with the stripe_count and stripe_unit parameters reversed. So if you have an rbd storage pool, and you do "virsh vol-create-as" or something equivalent, then instead of a stripe count of one and a stripe size of 4MB, you get 4194304 1-byte stripes. Needless to say, this renders the volume excruciatingly slow to the point of not being usable. Volume deletion also takes on the order of minutes even for an empty volume. This issue was introduced in libvirt 1.2.1, and was fixed for 1.2.4, but Ubuntu 14.04 LTS (which is on 1.2.2) evidently never backported that fix. So if you are on libvirt 1.2.2, libvirt rbd storage pools won't work for you unless you manually apply this patch: http://libvirt.org/git/?p=libvirt.git;a=commit;h=4cd508ba4fc3cc33c72629fe8b9012e73d8dd8bf Further information: Original Red Hat BZ: https://bugzilla.redhat.com/show_bug.cgi?id=1092208 Bug I just added to Launchpad so the Ubuntu folks (hopefully) backport the patch for trusty-updates: https://bugs.launchpad.net/ubuntu/+source/libvirt/+bug/1447030 Hope this is useful. Thanks to Steven McDonald from Anchor for spotting the original issue. Cheers, Florian _______________________________________________ ceph-users mailing list ceph-users@xxxxxxxxxxxxxx http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
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