- Multiple instances stop randomly.
- We can see 'Out of memory' errors on the host.
- We can see 'Instance is already powered off in the hypervisor when a stop is called' messages in /var/log/pf9/ostackhost.log on the host.
118 WARNING nova.compute.manager [req-f9189bc9-4218-494b-b794-a924fc744210 None None] [instance: baebf3af-6294-4e4c-ab9e-64f5f5ff45d7] Instance shutdown by itself. Calling the stop API. Current vm_state: active, current task_state: None, original DB power_state: 1, current VM power_state: 4
798 INFO nova.compute.manager [req-f9189bc9-4218-494b-b794-a924fc744210 None None] [instance: baebf3af-6294-4e4c-ab9e-64f5f5ff45d7] Instance is already powered off in the hypervisor when stop is called.
- We can see below errors in /var/log/messages.log.
smc02e3b01 kernel: Out of memory: Kill process 16752 (qemu-kvm) score 702 or sacrifice child
smc02e3b01 kernel: Killed process 16752 (qemu-kvm) total-vm:30600032kB, anon-rss:24304276kB, file-rss:2000kB, shmem-rss:20kB
smc02e3b01 systemd-machined: Machine qemu-15-baebf3af-6294-4e4c-ab9e-64f5f5ff45d7 terminated
- Platform9 Managed OpenStack - All Versions
Kernel initiated Out Of Memory Killer (OOM Killer).
OOM Killer is a process that the Linux kernel employs when the system is critically low on memory.
As there is not enough memory on the host, the kernel has initiated the OOM killer which sacrificed the qemu/kvm process and the instances on the host have stopped.
Add more memory on the host or increase swap if physical memory/swap space is low.