Re: Block Migration and xbzrle

Peter Lieven
2012-10-02T09:44:12Z

Am 02.10.2012 um 11:38 schrieb Paolo Bonzini:

> Il 16/09/2012 12:39, Peter Lieven ha scritto:
>>
>> I remember that this was broken some time ago and currently with
>> qemu-kvm 1.2.0 I am still not able to use
>> block migration plus xbzrle. The migration fails if both are used
>> together. XBZRLE without block migration works.
>>
>> Can someone please advise what is the current expected behaviour?
>
> Block migration is broken by design. It will converge really slowly as
> soon as you have real load in the VMs, and it will hamper the
> convergence of RAM as well.
>
> Hopefully a real alternative will be in 1.3 (based on drive-mirror on
> the source + an embedded NBD server running on the destination), then in
> 1.4 we can reimplement the block migration monitor commands using the
> alternative.

Hi Paolo, i know that block migration is not that good, but it seems that
there is a bug in XBZRLE that is independent of block migration.

Peter

>
> Paolo