What is significantly smaller? We have 67 requests in the 16,400,000 range and 250 in the 18,900,000 range.
Thanks, Adam On Wed, Apr 15, 2015 at 8:38 PM, Yan, Zheng <uker...@gmail.com> wrote: > On Thu, Apr 16, 2015 at 9:07 AM, Adam Tygart <mo...@ksu.edu> wrote: >> We are using 3.18.6-gentoo. Based on that, I was hoping that the >> kernel bug referred to in the bug report would have been fixed. >> > > The bug was supposed to be fixed, but you hit the bug again. could you > check if the kernel client has any hang mds request. (check > /sys/kernel/debug/ceph/*/mdsc on the machine that contain cephfs > mount. If there is any request whose ID is significant smaller than > other requests' IDs) > > Regards > Yan, Zheng > >> -- >> Adam >> >> On Wed, Apr 15, 2015 at 8:02 PM, Yan, Zheng <uker...@gmail.com> wrote: >>> On Thu, Apr 16, 2015 at 5:29 AM, Kyle Hutson <kylehut...@ksu.edu> wrote: >>>> Thank you, John! >>>> >>>> That was exactly the bug we were hitting. My Google-fu didn't lead me to >>>> this one. >>> >>> >>> here is the bug report http://tracker.ceph.com/issues/10449. It's a >>> kernel client bug which causes the session map size increase >>> infinitely. which version of linux kernel are using? >>> >>> Regards >>> Yan, Zheng >>> >>> >>>> >>>> On Wed, Apr 15, 2015 at 4:16 PM, John Spray <john.sp...@redhat.com> wrote: >>>>> >>>>> On 15/04/2015 20:02, Kyle Hutson wrote: >>>>>> >>>>>> I upgraded to 0.94.1 from 0.94 on Monday, and everything had been going >>>>>> pretty well. >>>>>> >>>>>> Then, about noon today, we had an mds crash. And then the failover mds >>>>>> crashed. And this cascaded through all 4 mds servers we have. >>>>>> >>>>>> If I try to start it ('service ceph start mds' on CentOS 7.1), it appears >>>>>> to be OK for a little while. ceph -w goes through 'replay' 'reconnect' >>>>>> 'rejoin' 'clientreplay' and 'active' but nearly immediately after >>>>>> getting to >>>>>> 'active', it crashes again. >>>>>> >>>>>> I have the mds log at >>>>>> http://people.beocat.cis.ksu.edu/~kylehutson/ceph-mds.hobbit01.log >>>>>> <http://people.beocat.cis.ksu.edu/%7Ekylehutson/ceph-mds.hobbit01.log> >>>>>> >>>>>> For the possibly, but not necessarily, useful background info. >>>>>> - Yesterday we took our erasure coded pool and increased both pg_num and >>>>>> pgp_num from 2048 to 4096. We still have several objects misplaced >>>>>> (~17%), >>>>>> but those seem to be continuing to clean themselves up. >>>>>> - We are in the midst of a large (300+ TB) rsync from our old (non-ceph) >>>>>> filesystem to this filesystem. >>>>>> - Before we realized the mds crashes, we had just changed the size of our >>>>>> metadata pool from 2 to 4. >>>>> >>>>> >>>>> It looks like you're seeing http://tracker.ceph.com/issues/10449, which is >>>>> a situation where the SessionMap object becomes too big for the MDS to >>>>> save.The cause of it in that case was stuck requests from a misbehaving >>>>> client running a slightly older kernel. >>>>> >>>>> Assuming you're using the kernel client and having a similar problem, you >>>>> could try to work around this situation by forcibly unmounting the clients >>>>> while the MDS is offline, such that during clientreplay the MDS will >>>>> remove >>>>> them from the SessionMap after timing out, and then next time it tries to >>>>> save the map it won't be oversized. If that works, you could then look >>>>> into >>>>> getting newer kernels on the clients to avoid hitting the issue again -- >>>>> the >>>>> #10449 ticket has some pointers about which kernel changes were relevant. >>>>> >>>>> Cheers, >>>>> John >>>> >>>> >>>> >>>> _______________________________________________ >>>> ceph-users mailing list >>>> ceph-users@lists.ceph.com >>>> http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com >>>> >>> _______________________________________________ >>> ceph-users mailing list >>> ceph-users@lists.ceph.com >>> http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com _______________________________________________ ceph-users mailing list ceph-users@lists.ceph.com http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
