On Wed, Nov 16, 2016 at 12:18 PM, Burkhard Linke <Burkhard.Linke@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx> wrote: > Hi, > > > On 11/16/2016 11:17 AM, John Spray wrote: >> >> On Wed, Nov 16, 2016 at 1:16 AM, Patrick Donnelly <pdonnell@xxxxxxxxxx> >> wrote: >>> >>> On Tue, Nov 15, 2016 at 8:40 AM, Hauke Homburg <hhomburg@xxxxxxxxxxxxxx> >>> wrote: >>>> >>>> In the last weeks we enabled for testing the dir fragmentation. The >>>> Resultat >>>> is that we have sometimes error messages with rsync with unlink and >>>> no-space >>>> left on device. >>> >>> Enabling directory fragmentation would not cause the unlink and ENOSPC >>> errors. Failure to unlink is caused by the stray directories on the >>> MDS growing too large. The only current solution is to wait for the >>> MDS to eventually purge the stray directory entries. Retry the unlink >>> as necessary. [The other workaround is to increase >>> mds_bal_fragment_size_max [1] which is not recommended.] >>> >>> Directory fragmentation is not yet considered stable so beware >>> potential issues including data loss. However, fragmentation will >>> allow your directories to grow to unbounded size. This includes the >>> stray directories which would permit unlink to avoid this issue. >> >> The last part isn't quite right, we currently don't fragment >> strays[1]. Unfortunately anyone who uses directory fragmentation to >> create a super-big directory could still have issues when unlinking >> it. However, there are 10x stray directories and removed items are >> spread between them, so you should be able to handle deleting a >> directory 10x the limit on the size of a stray dir. > > Just out of curiosity: > > It is possible to increase the number of stray directories? Nope, it's a compiled-in constant. John > Regards, > Burkhard > > -- > Dr. rer. nat. Burkhard Linke > Bioinformatics and Systems Biology > Justus-Liebig-University Giessen > 35392 Giessen, Germany > Phone: (+49) (0)641 9935810 > > > _______________________________________________ > 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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