From: Paolo Bonzini <pbonzini@redhat.com>
To: Peter Lieven <pl@dlhnet.de>
Cc: "qemu-devel@nongnu.org" <qemu-devel@nongnu.org>,
"kvm@vger.kernel.org" <kvm@vger.kernel.org>
Subject: Re: Block Migration and xbzrle
Date: Tue, 02 Oct 2012 12:09:44 +0200 [thread overview]
Message-ID: <506ABD68.4060508@redhat.com> (raw)
In-Reply-To: <135E8E0A-174B-4A0A-ABF3-9B41F224F88A@dlhnet.de>
Il 02/10/2012 11:44, Peter Lieven ha scritto:
>
> 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.
Understood---but hopefully you can stop using it with 1.3, which would
also work around the bug. :)
Paolo
WARNING: multiple messages have this Message-ID (diff)
From: Paolo Bonzini <pbonzini@redhat.com>
To: Peter Lieven <pl@dlhnet.de>
Cc: "qemu-devel@nongnu.org" <qemu-devel@nongnu.org>,
"kvm@vger.kernel.org" <kvm@vger.kernel.org>
Subject: Re: [Qemu-devel] Block Migration and xbzrle
Date: Tue, 02 Oct 2012 12:09:44 +0200 [thread overview]
Message-ID: <506ABD68.4060508@redhat.com> (raw)
In-Reply-To: <135E8E0A-174B-4A0A-ABF3-9B41F224F88A@dlhnet.de>
Il 02/10/2012 11:44, Peter Lieven ha scritto:
>
> 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.
Understood---but hopefully you can stop using it with 1.3, which would
also work around the bug. :)
Paolo
next prev parent reply other threads:[~2012-10-02 10:09 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-09-16 10:39 Block Migration and xbzrle Peter Lieven
2012-09-16 10:39 ` [Qemu-devel] " Peter Lieven
2012-09-17 18:03 ` Orit Wasserman
2012-10-02 8:33 ` lieven-lists
2012-10-02 9:28 ` Orit Wasserman
2012-10-02 9:30 ` Peter Lieven
2012-10-02 9:30 ` Peter Lieven
2012-10-02 10:40 ` Orit Wasserman
2012-10-02 10:40 ` [Qemu-devel] " Orit Wasserman
2012-10-04 6:31 ` Peter Lieven
2012-10-04 6:31 ` Peter Lieven
2012-10-02 9:38 ` Paolo Bonzini
2012-10-02 9:38 ` [Qemu-devel] " Paolo Bonzini
2012-10-02 9:44 ` Peter Lieven
2012-10-02 9:44 ` [Qemu-devel] " Peter Lieven
2012-10-02 10:09 ` Paolo Bonzini [this message]
2012-10-02 10:09 ` Paolo Bonzini
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