Re: [Qemu-devel] live migration vs device assignment (motivation)

2016-01-03 Thread Lan Tianyu
On 2015年12月30日 00:46, Michael S. Tsirkin wrote: > Interesting. So you sare saying merely ifdown/ifup is 100ms? > This does not sound reasonable. > Is there a chance you are e.g. getting IP from dhcp? > > If so that is wrong - clearly should reconfigure the old IP > back without playing with dhcp.

Re: [Qemu-devel] live migration vs device assignment (motivation)

2015-12-29 Thread Alexander Duyck
On Tue, Dec 29, 2015 at 9:15 AM, Michael S. Tsirkin wrote: > On Tue, Dec 29, 2015 at 09:04:51AM -0800, Alexander Duyck wrote: >> On Tue, Dec 29, 2015 at 8:46 AM, Michael S. Tsirkin wrote: >> > On Tue, Dec 29, 2015 at 01:42:14AM +0800, Lan, Tianyu wrote: >> >> >> >> >> >> On 12/25/2015 8:11 PM, Mi

Re: [Qemu-devel] live migration vs device assignment (motivation)

2015-12-29 Thread Michael S. Tsirkin
On Tue, Dec 29, 2015 at 09:04:51AM -0800, Alexander Duyck wrote: > On Tue, Dec 29, 2015 at 8:46 AM, Michael S. Tsirkin wrote: > > On Tue, Dec 29, 2015 at 01:42:14AM +0800, Lan, Tianyu wrote: > >> > >> > >> On 12/25/2015 8:11 PM, Michael S. Tsirkin wrote: > >> >As long as you keep up this vague tal

Re: [Qemu-devel] live migration vs device assignment (motivation)

2015-12-29 Thread Alexander Duyck
On Tue, Dec 29, 2015 at 8:46 AM, Michael S. Tsirkin wrote: > On Tue, Dec 29, 2015 at 01:42:14AM +0800, Lan, Tianyu wrote: >> >> >> On 12/25/2015 8:11 PM, Michael S. Tsirkin wrote: >> >As long as you keep up this vague talk about performance during >> >migration, without even bothering with any mea

Re: [Qemu-devel] live migration vs device assignment (motivation)

2015-12-29 Thread Michael S. Tsirkin
On Tue, Dec 29, 2015 at 01:42:14AM +0800, Lan, Tianyu wrote: > > > On 12/25/2015 8:11 PM, Michael S. Tsirkin wrote: > >As long as you keep up this vague talk about performance during > >migration, without even bothering with any measurements, this patchset > >will keep going nowhere. > > > > I m

Re: [Qemu-devel] live migration vs device assignment (motivation)

2015-12-28 Thread Lan, Tianyu
On 12/25/2015 8:11 PM, Michael S. Tsirkin wrote: As long as you keep up this vague talk about performance during migration, without even bothering with any measurements, this patchset will keep going nowhere. I measured network service downtime for "keep device alive"(RFC patch V1 presented

Re: [Qemu-devel] live migration vs device assignment (motivation)

2015-12-28 Thread Michael S. Tsirkin
On Mon, Dec 28, 2015 at 11:52:43AM +0300, Pavel Fedin wrote: > Hello! > > > A dedicated IRQ per device for something that is a system wide event > > sounds like a waste. I don't understand why a spec change is strictly > > required, we only need to support this with the specific virtual bridge >

Re: [Qemu-devel] live migration vs device assignment (motivation)

2015-12-28 Thread Michael S. Tsirkin
On Mon, Dec 28, 2015 at 03:20:10AM +, Dong, Eddie wrote: > > > > > > Even if the device driver doesn't support migration, you still want to > > > migrate VM? That maybe risk and we should add the "bad path" for the > > > driver at least. > > > > At a minimum we should have support for hot-plug

Re: [Qemu-devel] live migration vs device assignment (motivation)

2015-12-28 Thread Pavel Fedin
Hello! > A dedicated IRQ per device for something that is a system wide event > sounds like a waste. I don't understand why a spec change is strictly > required, we only need to support this with the specific virtual bridge > used by QEMU, so I think that a vendor specific capability will do. >

Re: [Qemu-devel] live migration vs device assignment (motivation)

2015-12-28 Thread Michael S. Tsirkin
On Sun, Dec 27, 2015 at 01:45:15PM -0800, Alexander Duyck wrote: > On Sun, Dec 27, 2015 at 1:21 AM, Michael S. Tsirkin wrote: > > On Fri, Dec 25, 2015 at 02:31:14PM -0800, Alexander Duyck wrote: > >> The PCI hot-plug specification calls out that the OS can optionally > >> implement a "pause" mecha

Re: [Qemu-devel] live migration vs device assignment (motivation)

2015-12-27 Thread Alexander Duyck
On Sun, Dec 27, 2015 at 7:20 PM, Dong, Eddie wrote: >> > >> > Even if the device driver doesn't support migration, you still want to >> > migrate VM? That maybe risk and we should add the "bad path" for the >> > driver at least. >> >> At a minimum we should have support for hot-plug if we are expe

Re: [Qemu-devel] live migration vs device assignment (motivation)

2015-12-27 Thread Dong, Eddie
> > > > Even if the device driver doesn't support migration, you still want to > > migrate VM? That maybe risk and we should add the "bad path" for the > > driver at least. > > At a minimum we should have support for hot-plug if we are expecting to > support migration. You would simply have to ho

Re: [Qemu-devel] live migration vs device assignment (motivation)

2015-12-27 Thread Alexander Duyck
On Sun, Dec 27, 2015 at 1:21 AM, Michael S. Tsirkin wrote: > On Fri, Dec 25, 2015 at 02:31:14PM -0800, Alexander Duyck wrote: >> The PCI hot-plug specification calls out that the OS can optionally >> implement a "pause" mechanism which is meant to be used for high >> availability type environments

Re: [Qemu-devel] live migration vs device assignment (motivation)

2015-12-27 Thread Michael S. Tsirkin
On Fri, Dec 25, 2015 at 02:31:14PM -0800, Alexander Duyck wrote: > The PCI hot-plug specification calls out that the OS can optionally > implement a "pause" mechanism which is meant to be used for high > availability type environments. What I am proposing is basically > extending the standard SHPC

Re: [Qemu-devel] live migration vs device assignment (motivation)

2015-12-25 Thread Alexander Duyck
On Thu, Dec 24, 2015 at 11:03 PM, Lan Tianyu wrote: > Merry Christmas. > Sorry for later response due to personal affair. > > On 2015年12月14日 03:30, Alexander Duyck wrote: >>> > These sounds we need to add a faked bridge for migration and adding a >>> > driver in the guest for it. It also needs to

Re: [Qemu-devel] live migration vs device assignment (motivation)

2015-12-25 Thread Michael S. Tsirkin
On Fri, Dec 25, 2015 at 03:03:47PM +0800, Lan Tianyu wrote: > Merry Christmas. > Sorry for later response due to personal affair. > > On 2015年12月14日 03:30, Alexander Duyck wrote: > >> > These sounds we need to add a faked bridge for migration and adding a > >> > driver in the guest for it. It also

Re: [Qemu-devel] live migration vs device assignment (motivation)

2015-12-24 Thread Lan Tianyu
Merry Christmas. Sorry for later response due to personal affair. On 2015年12月14日 03:30, Alexander Duyck wrote: >> > These sounds we need to add a faked bridge for migration and adding a >> > driver in the guest for it. It also needs to extend PCI bus/hotplug >> > driver to do pause/resume other de

Re: [Qemu-devel] live migration vs device assignment (motivation)

2015-12-14 Thread Michael S. Tsirkin
On Sun, Dec 13, 2015 at 11:47:44PM +0800, Lan, Tianyu wrote: > > > On 12/11/2015 1:16 AM, Alexander Duyck wrote: > >On Thu, Dec 10, 2015 at 6:38 AM, Lan, Tianyu wrote: > >> > >> > >>On 12/10/2015 7:41 PM, Dr. David Alan Gilbert wrote: > > Ideally, it is able to leave guest driver unmodi

Re: [Qemu-devel] live migration vs device assignment (motivation)

2015-12-14 Thread Michael S. Tsirkin
On Fri, Dec 11, 2015 at 03:32:04PM +0800, Lan, Tianyu wrote: > > > On 12/11/2015 12:11 AM, Michael S. Tsirkin wrote: > >On Thu, Dec 10, 2015 at 10:38:32PM +0800, Lan, Tianyu wrote: > >> > >> > >>On 12/10/2015 7:41 PM, Dr. David Alan Gilbert wrote: > Ideally, it is able to leave guest driver u

Re: [Qemu-devel] live migration vs device assignment (motivation)

2015-12-13 Thread Alexander Duyck
On Sun, Dec 13, 2015 at 7:47 AM, Lan, Tianyu wrote: > > > On 12/11/2015 1:16 AM, Alexander Duyck wrote: >> >> On Thu, Dec 10, 2015 at 6:38 AM, Lan, Tianyu wrote: >>> >>> >>> >>> On 12/10/2015 7:41 PM, Dr. David Alan Gilbert wrote: > > > Ideally, it is able to leave guest driver unmodi

Re: [Qemu-devel] live migration vs device assignment (motivation)

2015-12-13 Thread Lan, Tianyu
On 12/11/2015 1:16 AM, Alexander Duyck wrote: On Thu, Dec 10, 2015 at 6:38 AM, Lan, Tianyu wrote: On 12/10/2015 7:41 PM, Dr. David Alan Gilbert wrote: Ideally, it is able to leave guest driver unmodified but it requires the hypervisor or qemu to aware the device which means we may need a

Re: [Qemu-devel] live migration vs device assignment (motivation)

2015-12-10 Thread Lan, Tianyu
On 12/11/2015 12:11 AM, Michael S. Tsirkin wrote: On Thu, Dec 10, 2015 at 10:38:32PM +0800, Lan, Tianyu wrote: On 12/10/2015 7:41 PM, Dr. David Alan Gilbert wrote: Ideally, it is able to leave guest driver unmodified but it requires the hypervisor or qemu to aware the device which means we

Re: [Qemu-devel] live migration vs device assignment (motivation)

2015-12-10 Thread Alexander Duyck
On Thu, Dec 10, 2015 at 8:11 AM, Michael S. Tsirkin wrote: > On Thu, Dec 10, 2015 at 10:38:32PM +0800, Lan, Tianyu wrote: >> >> >> On 12/10/2015 7:41 PM, Dr. David Alan Gilbert wrote: >> >>Ideally, it is able to leave guest driver unmodified but it requires the >> >>>hypervisor or qemu to aware th

Re: [Qemu-devel] live migration vs device assignment (motivation)

2015-12-10 Thread Yang Zhang
On 2015/12/10 19:41, Dr. David Alan Gilbert wrote: * Yang Zhang (yang.zhang...@gmail.com) wrote: On 2015/12/10 18:18, Dr. David Alan Gilbert wrote: * Lan, Tianyu (tianyu@intel.com) wrote: On 12/8/2015 12:50 AM, Michael S. Tsirkin wrote: I thought about what this is doing at the high level

Re: [Qemu-devel] live migration vs device assignment (motivation)

2015-12-10 Thread Yang Zhang
On 2015/12/10 18:18, Dr. David Alan Gilbert wrote: * Lan, Tianyu (tianyu@intel.com) wrote: On 12/8/2015 12:50 AM, Michael S. Tsirkin wrote: I thought about what this is doing at the high level, and I do have some value in what you are trying to do, but I also think we need to clarify the mo

Re: [Qemu-devel] live migration vs device assignment (motivation)

2015-12-10 Thread Alexander Duyck
On Thu, Dec 10, 2015 at 6:38 AM, Lan, Tianyu wrote: > > > On 12/10/2015 7:41 PM, Dr. David Alan Gilbert wrote: >>> >>> Ideally, it is able to leave guest driver unmodified but it requires the >>> >hypervisor or qemu to aware the device which means we may need a driver >>> > in >>> >hypervisor or q

Re: [Qemu-devel] live migration vs device assignment (motivation)

2015-12-10 Thread Dr. David Alan Gilbert
* Lan, Tianyu (tianyu@intel.com) wrote: > > > On 12/10/2015 7:41 PM, Dr. David Alan Gilbert wrote: > >>Ideally, it is able to leave guest driver unmodified but it requires the > >>>hypervisor or qemu to aware the device which means we may need a driver in > >>>hypervisor or qemu to handle the

Re: [Qemu-devel] live migration vs device assignment (motivation)

2015-12-10 Thread Michael S. Tsirkin
On Thu, Dec 10, 2015 at 10:38:32PM +0800, Lan, Tianyu wrote: > > > On 12/10/2015 7:41 PM, Dr. David Alan Gilbert wrote: > >>Ideally, it is able to leave guest driver unmodified but it requires the > >>>hypervisor or qemu to aware the device which means we may need a driver in > >>>hypervisor or q

Re: [Qemu-devel] live migration vs device assignment (motivation)

2015-12-10 Thread Lan, Tianyu
On 12/10/2015 7:41 PM, Dr. David Alan Gilbert wrote: Ideally, it is able to leave guest driver unmodified but it requires the >hypervisor or qemu to aware the device which means we may need a driver in >hypervisor or qemu to handle the device on behalf of guest driver. Can you answer the quest

Re: [Qemu-devel] live migration vs device assignment (motivation)

2015-12-10 Thread Lan, Tianyu
On 12/10/2015 4:38 PM, Michael S. Tsirkin wrote: Let's assume you do save state and do have a way to detect whether state matches a given hardware. For example, driver could store firmware and hardware versions in the state, and then on destination, retrieve them and compare. It will be pretty co

Re: [Qemu-devel] live migration vs device assignment (motivation)

2015-12-10 Thread Dr. David Alan Gilbert
* Yang Zhang (yang.zhang...@gmail.com) wrote: > On 2015/12/10 18:18, Dr. David Alan Gilbert wrote: > >* Lan, Tianyu (tianyu@intel.com) wrote: > >>On 12/8/2015 12:50 AM, Michael S. Tsirkin wrote: > >>>I thought about what this is doing at the high level, and I do have some > >>>value in what you

Re: [Qemu-devel] live migration vs device assignment (motivation)

2015-12-10 Thread Dr. David Alan Gilbert
* Lan, Tianyu (tianyu@intel.com) wrote: > On 12/8/2015 12:50 AM, Michael S. Tsirkin wrote: > >I thought about what this is doing at the high level, and I do have some > >value in what you are trying to do, but I also think we need to clarify > >the motivation a bit more. What you are saying is

Re: [Qemu-devel] live migration vs device assignment (motivation)

2015-12-10 Thread Michael S. Tsirkin
On Thu, Dec 10, 2015 at 11:04:54AM +0800, Lan, Tianyu wrote: > > On 12/10/2015 4:07 AM, Michael S. Tsirkin wrote: > >On Thu, Dec 10, 2015 at 12:26:25AM +0800, Lan, Tianyu wrote: > >>On 12/8/2015 12:50 AM, Michael S. Tsirkin wrote: > >>>I thought about what this is doing at the high level, and I do

Re: [Qemu-devel] live migration vs device assignment (motivation)

2015-12-09 Thread Lan, Tianyu
On 12/10/2015 1:14 AM, Alexander Duyck wrote: On Wed, Dec 9, 2015 at 8:26 AM, Lan, Tianyu wrote: For other kind of devices, it's hard to work. We are also adding migration support for QAT(QuickAssist Technology) device. QAT device user case introduction. Server, networking, big data, and st

Re: [Qemu-devel] live migration vs device assignment (motivation)

2015-12-09 Thread Lan, Tianyu
On 12/10/2015 4:07 AM, Michael S. Tsirkin wrote: On Thu, Dec 10, 2015 at 12:26:25AM +0800, Lan, Tianyu wrote: On 12/8/2015 12:50 AM, Michael S. Tsirkin wrote: I thought about what this is doing at the high level, and I do have some value in what you are trying to do, but I also think we need t

Re: [Qemu-devel] live migration vs device assignment (motivation)

2015-12-09 Thread Michael S. Tsirkin
On Thu, Dec 10, 2015 at 12:26:25AM +0800, Lan, Tianyu wrote: > On 12/8/2015 12:50 AM, Michael S. Tsirkin wrote: > >I thought about what this is doing at the high level, and I do have some > >value in what you are trying to do, but I also think we need to clarify > >the motivation a bit more. What

Re: [Qemu-devel] live migration vs device assignment (motivation)

2015-12-09 Thread Alexander Duyck
On Wed, Dec 9, 2015 at 8:26 AM, Lan, Tianyu wrote: > For other kind of devices, it's hard to work. > We are also adding migration support for QAT(QuickAssist Technology) device. > > QAT device user case introduction. > Server, networking, big data, and storage applications use QuickAssist > Techn

Re: [Qemu-devel] live migration vs device assignment (motivation)

2015-12-09 Thread Lan, Tianyu
On 12/8/2015 12:50 AM, Michael S. Tsirkin wrote: I thought about what this is doing at the high level, and I do have some value in what you are trying to do, but I also think we need to clarify the motivation a bit more. What you are saying is not really what the patches are doing. And with tha