On 01/12/2014 06:39 PM, Stefan Hajnoczi wrote: > On Fri, Jan 10, 2014 at 11:50 AM, 叶绍琛 <yeshaoc...@foxmail.com> wrote: > > Please use Reply-all to keep the CC list in tact. That way the > conversation stays on the mailing list and others can participate. > >>> Is the sum of guests' RAM less than the total physical RAM on the host >> The host run 3 vms, each vm use one vcpu core and 1G ram. >> # free -m >> >> total used free shared buffers cached >> >> Mem: 32242 4808 27434 0 278 2058 >> >> -/+ buffers/cache: 2471 29771 >> >> Swap: 4095 0 4095 >> >> >> The host has 8 cores. >> # cat /proc/cpuinfo | grep processor >> processor : 0 >> processor : 1 >> processor : 2 >> processor : 3 >> processor : 4 >> processor : 5 >> processor : 6 >> processor : 7 >> >> so, both of two question's answer is 'yes'. >> When I runing random write test, the host use 0 swap. > > Great. That means the host is not overcommitted. > > It's likely that the problem is a bug in QEMU's rbd driver or librados. > > Josh: Perhaps something you're interested in looking into?
Yes, thanks for bringing it to my attention. It does sound like a bug in QEMU's rbd driver or ceph's userspace libraries. Could you share what version of librbd you're using, and your /etc/ceph/ceph.conf? Thanks, Josh
