Public bug reported: Hello,
Problem: KVM guest's CPU usage goest upto 100% and more (if multi-proc or multi-cores) and makes guest running slowly for period of time when the flush process is running on a virtio storage drive. How to get this problem: just start the guest with virtio storage driver and make the guest do some storage related work (ie apt-get install mc) and watch top. after 2-3 sec the cpu usage will go to 100% and guest will run slowly (so slow, that even munin processes cant do their work in 5 minutes and create an e-mail report, that there are various .lock files present) host: ubuntu 10.04.1 LTS 2.6.32-27-server x86_64 2x Intel(R) Xeon(R) CPU E5620 (total of 16 cpus for os) 12GB RAM 2x software raids: 160GB and 2TB the 160GB one is for system and 2TB one is for kvm images guest: Ubuntu 10.04.1 LTS Disk: virtio network: virtio PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND 869 root 20 0 0 0 0 S 117 0.0 0:17.80 flush-252:0 252 is the vda disk: monitor@monitor:~$ ls -l /dev/vda brw-rw---- 1 root disk 252, 0 2011-01-13 16:44 /dev/vda ** Affects: kvm (Ubuntu) Importance: Undecided Status: New -- You received this bug notification because you are a member of Ubuntu Server Team, which is subscribed to kvm in ubuntu. https://bugs.launchpad.net/bugs/703811 Title: kvm guest's cpu usage with virtio storage driver goes up to 100% because of flush process -- Ubuntu-server-bugs mailing list Ubuntu-server-bugs@lists.ubuntu.com Modify settings or unsubscribe at: https://lists.ubuntu.com/mailman/listinfo/ubuntu-server-bugs