migrate_speed not working as documented

[e100]

I have been playing with IPoIB on some used Infiniband gear.
One thing I want is faster live migration.

First I needed a faster cipher for SSH.
I got AES-NI working: http://forum.proxmox.com/threads/7539-Speed-up-the-VM-(storage)-migration?p=43121#post43121
Then I edited the cipher in QemuMigrate.pm to be aes128-cbc

But migration speed was still very slow.

I edited the VM config file and added:

migrate_speed: 1000

That caused the VM to crash after live migration each time I migrated, but it was fast!
After I removed the network card from the VM the above setting worked fine.

With a lower setting and a network card is would sometimes live migrate without crashing.

Nov 21 20:48:22 starting migration of VM 100 to node 'vm6' (192.168.8.6)
Nov 21 20:48:22 copying disk images
Nov 21 20:48:22 starting VM on remote node 'vm6'
Nov 21 20:48:23 starting migration tunnel
Nov 21 20:48:23 starting online/live migration
Nov 21 20:48:25 migration status: active (transferred 123869KB, remaining 869596KB), total 4211008KB)
Nov 21 20:48:27 migration status: active (transferred 544840KB, remaining 276152KB), total 4211008KB)
Nov 21 20:48:29 migration status: completed
Nov 21 20:48:29 migration speed: 682.67 MB/s
Nov 21 20:48:31 migration finished successfuly (duration 00:00:09)
TASK OK

The qm man page says:

-migrate_speed integer (0 - N)   (default=0)

                    Set maximum speed (in MB/s) for migrations. Value 0 is no limit.

Either the man page is wrong or there is a bug.
It was slow before I set a large migrate_speed so it is not unlimited by default.

 

[dietmar]

Either the man page is wrong or there is a bug.
It was slow before I set a large migrate_speed so it is not unlimited by default.

Just uploaded a fix - please can you update and test again.

 

[e100]

Just uploaded a fix - please can you update and test again.

After updating I changed QemuMigrate.pm to set aes128-cbc and rebooted both nodes.
Removed migrate_speed from my vm.conf file and started it.

Now the VM migrates at full speed without needing to set the migrate_speed.
Same as above nearly 700MB/sec
Thanks for the fix!