Hello, The issue reproduced again and it doesn't look like a swap problem. Some details: on the baremetal, from top: top - 08:08:52 up 5 days, 16:43, 3 users, load average: 36.19, 36.05, 36.05 Tasks: 493 total, 1 running, 492 sleeping, 0 stopped, 0 zombie %Cpu(s): 3.5 us, 87.9 sy, 0.0 ni, 8.6 id, 0.0 wa, 0.0 hi, 0.0 si, 0.0 st KiB Mem : 12357451+total, 14296000 free, 65634428 used, 43644088 buff/cache KiB Swap: 4194300 total, 4073868 free, 120432 used. 56953888 avail Mem 19158 qemu 20 0 0.098t 0.041t 10476 S 3650 35.6 13048:24 qemu-kvm The compute node has 36 CPUs and the usage is now 100%. There are more than 50 GB of memory still available on the baremetal. The swap is barely used, 120 MB. On compute node, from top: top - 05:11:58 up 1 day, 15:08, 2 users, load average: 40.46, 40.49, 40.74 %Cpu(s): 99.1 us, 0.7 sy, 0.0 ni, 0.0 id, 0.0 wa, 0.0 hi, 0.1 si, 0.1 st KiB Mem : 10296246+total, 78079936 free, 23671360 used, 1211160 buff/cache KiB Swap: 0 total, 0 free, 0 used. 78939968 avail Mem PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND 6032 qemu 20 0 10.601g 1.272g 12964 S 400.0 1.3 588:40.39 qemu-kvm 5673 qemu 20 0 10.602g 1.006g 13020 S 399.7 1.0 1161:47 qemu-kvm 5998 qemu 20 0 10.601g 1.192g 13028 S 367.9 1.2 1544:30 qemu-kvm 5951 qemu 20 0 10.601g 1.246g 13020 S 348.3 1.3 1547:38 qemu-kvm 5750 qemu 20 0 10.599g 990136 13060 S 339.1 1.0 1152:25 qemu-kvm 5752 qemu 20 0 10.598g 1.426g 13040 S 313.9 1.5 663:13.65 qemu-kvm .... There are more than 70 GB of memory available on the compute node. All VMs are using 100% their CPUs and they are not accessible anymore. Laurentiu În dum., 14 aug. 2016 la 21:44, Boris Derzhavets <bderzhavets at hotmail.com> a scris: > > > > ------------------------------ > *From:* centos-virt-bounces at centos.org <centos-virt-bounces at centos.org> > on behalf of Laurentiu Soica <laurentiu at soica.ro> > *Sent:* Sunday, August 14, 2016 10:17 AM > *To:* Discussion about the virtualization on CentOS > *Subject:* Re: [CentOS-virt] Nested KVM issue > > More details on the subject: > > I suppose it is a nested KVM issue because it raised after I enabled the > nested KVM feature. Without it, anyway, the second level VMs are unusable > in terms of performance. > > I am using CentOS 7 with: > > kernel: 3.10.0-327.22.2.el7.x86_64 > qemu-kvm:1.5.3-105.el7_2.4 > libvirt:1.2.17-13.el7_2.5 > > on both the baremetal and the compute VM. > > *Please, post* > > 1) # virsh dumpxml VM-L1 ( where on L1 level you expect nested KVM to > appear) > 2) Login into VM-L1 and run :- > # lsmod | grep kvm > 3) I need outputs from VM-L1 ( in case it is Compute Node ) > > # cat /etc/nova/nova.conf | grep virt_type > # cat /etc/nova/nova.conf | grep cpu_mode > > Boris. > > > > > > The only workaround now is to shutdown the compute VM and start it back > from baremetal with virsh start. > A simple restart of the compute node doesn't help. It looks like the > qemu-kvm process corresponding to the compute VM is the problem. > > Laurentiu > > În dum., 14 aug. 2016 la 00:19, Laurentiu Soica <laurentiu at soica.ro> a > scris: > >> Hello, >> >> I have an OpenStack setup in virtual environment on CentOS 7. >> >> The baremetal has *nested KVM* enabled and 1 compute node as a VM. >> >> Inside the compute node I have multiple VMs running. >> >> After about every 3 days the VMs get inaccessible and the compute node >> reports high CPU usage. The qemu-kvm process for each VM inside the compute >> node reports full CPU usage. >> >> Please help me with some hints to debug this issue. >> >> Thanks, >> Laurentiu >> > _______________________________________________ > CentOS-virt mailing list > CentOS-virt at centos.org > https://lists.centos.org/mailman/listinfo/centos-virt > -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.centos.org/pipermail/centos-virt/attachments/20160816/24998b4b/attachment-0006.html>