On Tue, Aug 20, 2013 at 4:56 PM, Petr Soukup <soukup@xxxxxxxxxx> wrote: > I am using ceph filesystem through ceph-fuse to store product photos and most of the time it works great. But if there is some problem on ceph server, my connected clients start acting crazy. Load on all servers with mounted ceph jumps very high, webserver and other services start to crash. > I think, that if ceph server is irresponsive, system creates some queue and as a result everything starts to fail. Simple solution for this is this command: > umount -fl /media/ceph && ceph-fuse /media/ceph > After that everything gets to normal in a few minutes. > > Is it possible to set some timeout to ceph-fuse or something? It is much better if reading photo from ceph will cause error than if everything fails at once. > > I am using ceph 0.61.7 (today upgraded to 0.61.8), 2x OSD, 1x MDS and 4x mon on different servers with Centos 6.4. > I am going to try 0.67, but I think that my main problem is configuration of ceph-fuse mount. I also tried newer kernel with support for mount ceph, but the kernel itself wasn't very stable. What kind of problems are you seeing on the ceph server? In general what you're seeing is the result of ceph-fuse behaving optimistically: it expects that, if there is a problem on the cluster, then the problem will be dealt with shortly. So while it has lots of internal timeouts, it doesn't issue an error to clients unless it gets one back from a server. Doing otherwise in a data-safe fashion would be more or less impossible. If you want to add timeouts I bet you could find a library that will intercept system calls and let you put a timeout around them. -Greg Software Engineer #42 @ http://inktank.com | http://ceph.com _______________________________________________ ceph-users mailing list ceph-users@xxxxxxxxxxxxxx http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
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