Thanks for tracking this down. It appears the libvirt needs to check whether or not the fast-diff map is invalid before attempting to use it. However, assuming the map is valid, I don't immediately see a difference between the libvirt and "rbd du" implementation. Can you provide a pastebin "debug rbd = 20" log dump for your 13 second case? On Fri, Jan 4, 2019 at 2:19 AM Tomasz Płaza <tomasz.plaza@xxxxxxxxxx> wrote: > > Konstantin, > > Thanks for reply. I've managed to unravel it partially. Somehow (did not look into srpm) starting from this version libvirt started to calculate real allocation if fastdiff feature is present on image. Doing "rbd object-map rebuild" on every image helped (do not know why it was needed - it is a new cluster with ceph version 12.2.7). > > Now the only problem is 25T image on which "virsh vol-info" takes 13s (rbd du takes 1s) compared to few minutes before, so the questions remains: > > - why it happened, > > - how to monitor/foresee this, > > - how to improve virsh vol-info if rbd du take less time to execute? > > > On 03.01.2019 at 13:51, Konstantin Shalygin wrote: > > After update to CentOS 7.6, libvirt was updated from 3.9 to 4.5. > Executing: "virsh vol-list ceph --details" makes libvirtd using 300% CPU > for 2 minutes to show volumes on rbd. Quick pick at tcpdump shows > accessing rbd_data.* which previous version of libvirtd did not need. > Ceph version is 12.2.7. > > Any help will be appreciated > > There is nothing special in libvirt 4.5, I was upgraded hypervisors to this version, still works flawless. > > > > k > > _______________________________________________ > ceph-users mailing list > ceph-users@xxxxxxxxxxxxxx > http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com [1] https://github.com/libvirt/libvirt/blob/600462834f4ec1955a9a48a1b6b4a390b9c31553/src/storage/storage_backend_rbd.c#L386 -- Jason _______________________________________________ ceph-users mailing list ceph-users@xxxxxxxxxxxxxx http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
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