Yeah, it's very likely a kernel bug (that no one managed to reduce to a simpler test case or even to reproduce it reliably with reasonable effort on a test system). 4.9 and earlier aren't affected as far as we can tell, we only encountered this after upgrading. But I think Bionic ships with a broken kernel. Try raising the issue with the ubuntu guys if you are using a distribution kernel. Paul 2018-09-18 21:23 GMT+02:00 Alfredo Daniel Rezinovsky <alfredo.rezinovsky@xxxxxxxxxxxxxxxxxxxxxxxx>: > MOMENT !!! > > "Some kernels (4.9+) sometime fail to return data when reading from a block > device under memory pressure." > > I dind't knew that was the problem. Can't I just dowgrade the kernel? > > There are known working versions o just need to be prior 4.9? > > > On 18/09/18 16:19, Paul Emmerich wrote: > > We built a work-around here: https://github.com/ceph/ceph/pull/23273 > Which hasn't been backported, but we'll ship 13.2.2 in our Debian > packages for the croit OS image. > > > Paul > > > 2018-09-18 21:10 GMT+02:00 Alfredo Daniel Rezinovsky > <alfredo.rezinovsky@xxxxxxxxxxxxxxxxxxxxxxxx>: > > Changed all my hardware. Now I have plenty of free ram. swap never needed, > low iowait and still > > 7fdbbb73e700 -1 bluestore(/var/lib/ceph/osd/ceph-6) _verify_csum bad > crc32c/0x1000 checksum at blob offset 0x1e000, got 0x6706be76, expected > 0x85a3fefe, device location [0x25ac04be000~1000], logical extent > 0x1e000~1000, object #2:fd955b81:::10000729cdb.00000006 > > It happens sometimes, in all my OSDs. > > Bluestore OSDs with data in HDD and block.db in SSD > > After running pg repair the pgs were always repaired. > > running ceph in ubuntu 13.2.1-1bionic > > -- > Alfredo Daniel Rezinovsky > Director de Tecnologías de Información y Comunicaciones > Facultad de Ingeniería - Universidad Nacional de Cuyo > > _______________________________________________ > ceph-users mailing list > ceph-users@xxxxxxxxxxxxxx > http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com > > > > -- > Alfredo Daniel Rezinovsky > Director de Tecnologías de Información y Comunicaciones > Facultad de Ingeniería - Universidad Nacional de Cuyo -- Paul Emmerich Looking for help with your Ceph cluster? Contact us at https://croit.io croit GmbH Freseniusstr. 31h 81247 München www.croit.io Tel: +49 89 1896585 90 _______________________________________________ ceph-users mailing list ceph-users@xxxxxxxxxxxxxx http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
 |