Re: ceph rbd crashes/stalls while random write 4k blocks

[Stefan Priebe - Profihost AG <s.priebe@profihost.ag>]

Am 24.05.2012 16:19, schrieb Florian Haas:
> On Thu, May 24, 2012 at 4:09 PM, Stefan Priebe - Profihost AG
> <s.priebe@profihost.ag> wrote:
>>> Take a look at these to see if anything looks familiar:
>>>
>>> http://oss.sgi.com/bugzilla/show_bug.cgi?id=922
>>> https://bugs.launchpad.net/ubuntu/+source/linux/+bug/979498
>>> http://oss.sgi.com/archives/xfs/2011-11/msg00400.html
>>
>> These are solved by using 3.0.20.
> 
> ... or so Christoph says, but comment #4 in bug 922 seems to indicate otherwise.

I'm sorry you're absolutely right. BUT XFS had some regressions with
xlog_grabt_log_space since 2.6.28 which was fixed in 3.0.X by reverting
back to a kernel thread instead of workers. I was working with Christoph
and Dave on this problem and it tooked be nearly a whole month to track
that down (git commit c7eead1e118fb7e34ee8f5063c3c090c054c3820). In this
case (#922) it seems it is really related to a too small log. But I
don't have a too small log in my ceph case ;-)

Stefan