Hi, Sometimes this problem happened in one day, but sometimes it was very difficult to reproduce it. Previously the clock source of the guest was kvm-clock. Now I changed it to tsc. The problem didn't occur until now. Is it related to the clock source? I find that there are some bug fixes for kvm-clock recently. (e.g., http://www.spinics.net/lists/stable-commits/msg11942.html) Anyway, I will update KVM later. Thanks, Paul On Wed, Aug 24, 2011 at 6:24 PM, Stefan Hajnoczi <stefanha@xxxxxxxxx> wrote: > > On Wed, Aug 24, 2011 at 10:02 AM, Xiao Guangrong > <xiaoguangrong@xxxxxxxxxxxxxx> wrote: > > On 08/24/2011 04:40 PM, Paul wrote: > >> Hi, > >> > >> I captured the output of pidstat when the problem was reproduced: > >> > >> bash-4.1# pidstat -p $PID 8966 > >> Linux 2.6.32-71.el6.x86_64 (test) 07/24/11 _x86_64_ (4 CPU) > >> > >> 16:25:15 PID %usr %system %guest %CPU CPU Command > >> 16:25:15 8966 0.14 55.04 115.41 170.59 1 qemu-kvm > >> > > > > I have tried to reproduce it, but it was failed. I am using the > > current KVM code. I suggest you to test it by the new code if possible. > > Yes, that's a good idea. The issue might already be fixed. But if > this is hard to reproduce then perhaps keep the spinning guest around > a bit longer so we can poke at it and figure out what is happening. > > The pidstat output shows us that it's the guest that is spinning, not > qemu-kvm userspace. > > The system time (time spent in host kernel) is also quite high so > running kvm_stat might show some interesting KVM events happening. > > Stefan -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
