Yes, this is what object-map does, it tracks used objects For your 50TB new image: - Without object-map, rbd rm must interate over every object, find out that the object does not exists, look after the next object etc - With object-map, rbd rm get the used objects list, find it empty, and job is done For rbd export, this may the the same However, rbd export exports a full image (so, in your case, 20TB) You may want to use rbd export-diff (which will still be some kind of slow without object-map, but will only output usefull data) Another tip: if you can, consider using rbd-nbd This allows you to mount a rbd volume using librbd On 03/17/2018 05:11 PM, shadow_lin wrote: > Hi list, > My ceph version is jewel 10.2.10. > I tired to use rbd rm to remove a 50TB image(without object map because krbd does't support it).It takes about 30mins to just complete about 3%. Is this expected? Is there a way to make it faster? > I know there are scripts to delete rados objects of the rbd image to make it faster. But is the slowness expected for rbd rm command? > > PS: I also encounter very slow rbd export for large rbd image(20TB image but with only a few GB data).Takes hours to completed the export.I guess both are related to object map not enabled, but krbd doesn't support object map feature. > > > > > 2018-03-18 > > > > shadowlin > > > > _______________________________________________ > 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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