Re: [Qemu-devel] [PATCH 0/17 v3] Localhost migration with side channel for ram

2013-11-27 Thread Andrea Arcangeli
On Tue, Nov 26, 2013 at 12:17:09PM +0100, Paolo Bonzini wrote: Il 26/11/2013 12:07, Lei Li ha scritto: For this, I am not quite sure I understand it correctly, seems the latest update of post copy migration was sent on last Oct, would you please give some insights on what else could I do

Re: [Qemu-devel] [PATCH 0/17 v3] Localhost migration with side channel for ram

2013-11-26 Thread Lei Li
On 11/25/2013 05:48 PM, Paolo Bonzini wrote: Il 25/11/2013 08:29, Lei Li ha scritto: In this case, if the migration would fail just because the misconfiguration of device state on destination, in the meantime the outgoing migration has no aware of this failure, I think it should add such

Re: [Qemu-devel] [PATCH 0/17 v3] Localhost migration with side channel for ram

2013-11-26 Thread Paolo Bonzini
Il 26/11/2013 12:07, Lei Li ha scritto: Basically, -incoming without -S is a broken option because of the missing handshake at the end of migration. With -S something else (either a human or a program) can check that everything went well and choose whether to restart the source or the

Re: [Qemu-devel] [PATCH 0/17 v3] Localhost migration with side channel for ram

2013-11-25 Thread Paolo Bonzini
Il 25/11/2013 08:29, Lei Li ha scritto: In this case, if the migration would fail just because the misconfiguration of device state on destination, in the meantime the outgoing migration has no aware of this failure, I think it should add such handling (like synchronize of the device

Re: [Qemu-devel] [PATCH 0/17 v3] Localhost migration with side channel for ram

2013-11-24 Thread Lei Li
On 11/22/2013 07:36 PM, Paolo Bonzini wrote: Il 22/11/2013 12:29, Lei Li ha scritto: During the page flipping migration, ram page of source guest would be flipped to the destination, that's why the source guest can not be resumed. AFAICT, the page flipping migration may fail at the connection

Re: [Qemu-devel] [PATCH 0/17 v3] Localhost migration with side channel for ram

2013-11-22 Thread Lei Li
On 11/21/2013 06:19 PM, Daniel P. Berrange wrote: On Thu, Nov 21, 2013 at 05:11:23PM +0800, Lei Li wrote: This patch series tries to introduce a mechanism using side channel pipe for RAM via SCM_RIGHTS with unix domain socket protocol migration. This side channel is used for the page flipping

Re: [Qemu-devel] [PATCH 0/17 v3] Localhost migration with side channel for ram

2013-11-22 Thread Paolo Bonzini
Il 22/11/2013 12:29, Lei Li ha scritto: During the page flipping migration, ram page of source guest would be flipped to the destination, that's why the source guest can not be resumed. AFAICT, the page flipping migration may fail at the connection stage (including the exchange of pipe fd) and

Re: [Qemu-devel] [PATCH 0/17 v3] Localhost migration with side channel for ram

2013-11-22 Thread Daniel P. Berrange
On Fri, Nov 22, 2013 at 07:29:05PM +0800, Lei Li wrote: On 11/21/2013 06:19 PM, Daniel P. Berrange wrote: On Thu, Nov 21, 2013 at 05:11:23PM +0800, Lei Li wrote: In discussions about supporting this for libvirt, we were told that when this localhost migration fails, you cannot re-start the

[Qemu-devel] [PATCH 0/17 v3] Localhost migration with side channel for ram

2013-11-21 Thread Lei Li
This patch series tries to introduce a mechanism using side channel pipe for RAM via SCM_RIGHTS with unix domain socket protocol migration. This side channel is used for the page flipping by vmsplice, which is the internal mechanism for localhost migration that we are trying to add to QEMU. The

Re: [Qemu-devel] [PATCH 0/17 v3] Localhost migration with side channel for ram

2013-11-21 Thread Daniel P. Berrange
On Thu, Nov 21, 2013 at 05:11:23PM +0800, Lei Li wrote: This patch series tries to introduce a mechanism using side channel pipe for RAM via SCM_RIGHTS with unix domain socket protocol migration. This side channel is used for the page flipping by vmsplice, which is the internal mechanism