On Mon, 14 Nov 2011, Gregory Farnum wrote: > On Mon, Nov 14, 2011 at 5:33 AM, Martin Mailand <martin@xxxxxxxxxxxx> wrote: > > Hi Tomasz, > > as far as I know it still has this limit. > > But it should be relatively safe to use it. > > > > http://marc.info/?l=ceph-devel&m=131942130322957&w=2 > > > > If we hit the 4KB limit of xattrs in ext4 how does it show up in the rbd > > layer? > > > > How does it show up in the fs layer, would the fs still be clean? > > Right now it would show up very badly, unfortunately. (And yes, the > limit is still there.) You'd notice, though you might manage to > corrupt some of your data first. :/ Well, the osd's are now more careful about being fail-stop, so if they hit the xattr limit they crash. So there won't be data corruption per se, except that you won't be able to start the OSD up again because the journal replay will keep hitting the limit. > However, if you're not taking snapshots and you're not using xattrs > yourself, you won't hit it with rbd or the Ceph FS. Right. Nothing sets large xattrs on objects in rbd. For the file system, this would only happen on extremely (!) deeply nested directories (ceph dfs xattrs are managed by the MDS, not as object attrs). sage > -Greg > > > > > -martin > > > > > > Am 14.11.2011 14:09, schrieb Tomasz Paszkowski: > >> > >> what about limit on xattr size ? Is it still limited to 4KB ? > >> > >> > >> > >> On Mon, Nov 14, 2011 at 1:15 PM, Martin Mailand<martin@xxxxxxxxxxxx> > >> wrote: > >>> > >>> Hi Christian, > >>> I am not sure if you noticed, but your ext4 bug is fixed in mainline. I > >>> am > >>> running a ceph cluster with 40+ vms for over a week by now, without any > >>> problems. An fsck.ext4 shows the ext4 is clean. > >>> The performance of ext4 is much better than btrfs, no rise in the load of > >>> the osd's. > >>> > >>> -martin > >>> -- > >>> To unsubscribe from this list: send the line "unsubscribe ceph-devel" in > >>> the body of a message to majordomo@xxxxxxxxxxxxxxx > >>> More majordomo info at http://vger.kernel.org/majordomo-info.html > >>> > >> > >> > >> > > > > -- > > To unsubscribe from this list: send the line "unsubscribe ceph-devel" in > > the body of a message to majordomo@xxxxxxxxxxxxxxx > > More majordomo info at http://vger.kernel.org/majordomo-info.html > > > -- > To unsubscribe from this list: send the line "unsubscribe ceph-devel" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html > >
