Proxmox 4.4-13 Restore Issue


Jun 1, 2014
I use Proxmox 4.4-13 (latest version) with LVM-thin store on a HP RAID with 4 SSDs (RAID 10).
I'm currently migrating some VMs from a Proxmox 3.4-16 installation. I backed up a VM (qcow2/local) with Snapshot mode and gzip 2 compression to a NFS data store.

When I restore the backup to the LVM Thin Pool from the NFS data store it is quite fast at first but then the restore process hangs, IO Delay is 100% on ~3 cores while there is no disk activity. After about half an hour the restore process continues for 5-6 percent but then stops again. Now the restore is at 100%, huge IO delay, no disk activity and a kernel error. After waiting for an hour again the backup is complete and everything is normal again. However the backup is only 20 GB big.
I have attached the kernel error message and backup log.

While the backup is restoring I get a "CPU stuck for 120 seconds" in any KVM that is running at that time and even when all VMs are stopped the issue occurs.´

Note: The restore process writes with about 450 MB/s at first so it's definitely not a disk issue.

Best regards,



Aug 6, 2014
Hello all,

I had the same problem yesterday. Backup of all VMs to nfs. Renew the Server from 3.4 to 4.4.x (completely new installation on newly build raid), Thin-LMV as default. Update to 4.4.13......reboot....
During restore of single machines, the rest of the already restored and running machines were blocked or even crashed. Problems with the block-device.
System HP-Proliant with Smartarray - Raid 5, normal disks.

At the moment all are running but still seem instable.



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