How to restore backup of virtual machines in proxmox ve?

Question

linux

Unexpectedly, automatic backup of virtual machines stopped working in the Proxmox VE 3.4-11 virtualization system. The problem only occurs when the virtual machine is stopped for copying. When copying using snapshot, everything is OK,
Virtual machine: MS Windows 2008 R2 64-bit. Balooning is not used (no driver installed).
From the logs it is clear that something with memory allocation. But how to treat is not clear. The server is lightly loaded. At any time there is free 40 Gb of memory.
I would be grateful for any ideas.

INFO: update VM 101: -lock backup
INFO: backup mode: stop
INFO: ionice priority: 7
INFO: stopping vm
INFO: creating archive '/backup/dump/vzdump-qemu-101-2015_09_21-08_53_43.vma.lzo'
INFO: starting kvm to execute backup task
kvm: cannot set up guest memory 'pc.ram': Cannot allocate memory
INFO: restarting vm
INFO: vm is online again after 20 seconds

Answer 1

Study the official forum, ask a question there.
Although, to be honest, I see no reason to stop virtual machines. I myself only backup one, there openfire eats memory - I fly by turning off and on the entire system 8)))