Public bug reported: HP DL380 G9 Openstack (Kilo 2015.1.4) hypervisor 755GB RAM/2x18 core E5-2699v3 2.30GHz Ubuntu 14.04.3 with 4.4.0-28-generic kernel Qemu version 2.0.0+dfsg-2ubuntu1.22 Libvirt 1.2.2-0ubuntu13.1.16
Up to about 100 instances residing on the hypervisor, no issues are noticed. Once the server obtains about 100 instances, you see ksoftirqd process jump to the top of processes consuming CPU. Load shoots into the high 100's and low 200's and instances become inaccessible as the hypervisor begins dropping packets (due to CPU). Moved to Libvirt 1.2.2-0ubuntu13.1.17, qemu 2.0.0+dfsg-2ubuntu1.30, and kernel 3.13.0-101-generic. This appears to have resolved the issue and the server can once again handle 150+ instances without skipping a beat. I did find this error message repeated thousands of times in libvirtd.log up until kernel and package upgrade which fixed the issue: error : qemuMonitorJSONCheckError:354 : internal error: unable to execute QEMU command 'qom-get': guest hasn't updated any stats yet Let me know if I can provide extra detail Thanks ** Affects: qemu-kvm (Ubuntu) Importance: Undecided Status: New -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1646639 Title: KVM CPU slowdown on 4.4 kernel To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/qemu-kvm/+bug/1646639/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs