Re: [Qemu-devel] [QEMU PATCH v2] kvmclock: advance clock by time window between vm_stop and pre_save

2017-02-07 Thread Marcelo Tosatti
On Tue, Feb 07, 2017 at 06:02:13PM +0800, Wanpeng Li wrote: > 2016-11-08 3:41 GMT+08:00 Marcelo Tosatti : > > On Mon, Nov 07, 2016 at 03:46:11PM +, Dr. David Alan Gilbert wrote: > >> * Marcelo Tosatti (mtosa...@redhat.com) wrote: > >> > This patch, relative to pre-copy migration codepath, > >>

Re: [Qemu-devel] [QEMU PATCH v2] kvmclock: advance clock by time window between vm_stop and pre_save

2017-02-07 Thread Wanpeng Li
2016-11-08 3:41 GMT+08:00 Marcelo Tosatti : > On Mon, Nov 07, 2016 at 03:46:11PM +, Dr. David Alan Gilbert wrote: >> * Marcelo Tosatti (mtosa...@redhat.com) wrote: >> > This patch, relative to pre-copy migration codepath, >> > measures the time between vm_stop() and pre_save(), >> > which inclu

Re: [Qemu-devel] [QEMU PATCH v2] kvmclock: advance clock by time window between vm_stop and pre_save

2016-11-14 Thread Marcelo Tosatti
On Thu, Nov 10, 2016 at 06:57:21PM +0100, Paolo Bonzini wrote: > > > On 10/11/2016 12:48, Marcelo Tosatti wrote: > > Destination has to run the following logic: > > > > If (source has KVM_CAP_ADVANCE_CLOCK) > > use KVM_GET_CLOCK value > > Else > >read pvclock from guest > > > > To suppo

Re: [Qemu-devel] [QEMU PATCH v2] kvmclock: advance clock by time window between vm_stop and pre_save

2016-11-10 Thread Paolo Bonzini
On 10/11/2016 12:48, Marcelo Tosatti wrote: > Destination has to run the following logic: > > If (source has KVM_CAP_ADVANCE_CLOCK) > use KVM_GET_CLOCK value > Else >read pvclock from guest > > To support migration from older QEMU versions which do not have > KVM_CAP_ADVANCE_CLOCK (or n

Re: [Qemu-devel] [QEMU PATCH v2] kvmclock: advance clock by time window between vm_stop and pre_save

2016-11-10 Thread Marcelo Tosatti
GOn Wed, Nov 09, 2016 at 05:23:50PM +0100, Paolo Bonzini wrote: > > > On 08/11/2016 11:22, Dr. David Alan Gilbert wrote: > > * Marcelo Tosatti (mtosa...@redhat.com) wrote: > >> On Mon, Nov 07, 2016 at 08:03:50PM +, Dr. David Alan Gilbert wrote: > >>> * Marcelo Tosatti (mtosa...@redhat.com) wr

Re: [Qemu-devel] [QEMU PATCH v2] kvmclock: advance clock by time window between vm_stop and pre_save

2016-11-09 Thread Marcelo Tosatti
On Tue, Nov 08, 2016 at 11:32:30AM -0200, Marcelo Tosatti wrote: > On Tue, Nov 08, 2016 at 10:22:56AM +, Dr. David Alan Gilbert wrote: > > * Marcelo Tosatti (mtosa...@redhat.com) wrote: > > > On Mon, Nov 07, 2016 at 08:03:50PM +, Dr. David Alan Gilbert wrote: > > > > * Marcelo Tosatti (mtos

Re: [Qemu-devel] [QEMU PATCH v2] kvmclock: advance clock by time window between vm_stop and pre_save

2016-11-09 Thread Paolo Bonzini
On 09/11/2016 17:28, Dr. David Alan Gilbert wrote: > * Paolo Bonzini (pbonz...@redhat.com) wrote: >> >> >> On 08/11/2016 11:22, Dr. David Alan Gilbert wrote: >>> * Marcelo Tosatti (mtosa...@redhat.com) wrote: On Mon, Nov 07, 2016 at 08:03:50PM +, Dr. David Alan Gilbert wrote: > * Mar

Re: [Qemu-devel] [QEMU PATCH v2] kvmclock: advance clock by time window between vm_stop and pre_save

2016-11-09 Thread Dr. David Alan Gilbert
* Paolo Bonzini (pbonz...@redhat.com) wrote: > > > On 08/11/2016 11:22, Dr. David Alan Gilbert wrote: > > * Marcelo Tosatti (mtosa...@redhat.com) wrote: > >> On Mon, Nov 07, 2016 at 08:03:50PM +, Dr. David Alan Gilbert wrote: > >>> * Marcelo Tosatti (mtosa...@redhat.com) wrote: > On Mon,

Re: [Qemu-devel] [QEMU PATCH v2] kvmclock: advance clock by time window between vm_stop and pre_save

2016-11-09 Thread Paolo Bonzini
On 08/11/2016 11:22, Dr. David Alan Gilbert wrote: > * Marcelo Tosatti (mtosa...@redhat.com) wrote: >> On Mon, Nov 07, 2016 at 08:03:50PM +, Dr. David Alan Gilbert wrote: >>> * Marcelo Tosatti (mtosa...@redhat.com) wrote: On Mon, Nov 07, 2016 at 03:46:11PM +, Dr. David Alan Gilbert w

Re: [Qemu-devel] [QEMU PATCH v2] kvmclock: advance clock by time window between vm_stop and pre_save

2016-11-08 Thread Marcelo Tosatti
On Tue, Nov 08, 2016 at 10:22:56AM +, Dr. David Alan Gilbert wrote: > * Marcelo Tosatti (mtosa...@redhat.com) wrote: > > On Mon, Nov 07, 2016 at 08:03:50PM +, Dr. David Alan Gilbert wrote: > > > * Marcelo Tosatti (mtosa...@redhat.com) wrote: > > > > On Mon, Nov 07, 2016 at 03:46:11PM +,

Re: [Qemu-devel] [QEMU PATCH v2] kvmclock: advance clock by time window between vm_stop and pre_save

2016-11-08 Thread Dr. David Alan Gilbert
* Marcelo Tosatti (mtosa...@redhat.com) wrote: > On Mon, Nov 07, 2016 at 08:03:50PM +, Dr. David Alan Gilbert wrote: > > * Marcelo Tosatti (mtosa...@redhat.com) wrote: > > > On Mon, Nov 07, 2016 at 03:46:11PM +, Dr. David Alan Gilbert wrote: > > > > * Marcelo Tosatti (mtosa...@redhat.com) w

Re: [Qemu-devel] [QEMU PATCH v2] kvmclock: advance clock by time window between vm_stop and pre_save

2016-11-07 Thread Marcelo Tosatti
On Mon, Nov 07, 2016 at 08:03:50PM +, Dr. David Alan Gilbert wrote: > * Marcelo Tosatti (mtosa...@redhat.com) wrote: > > On Mon, Nov 07, 2016 at 03:46:11PM +, Dr. David Alan Gilbert wrote: > > > * Marcelo Tosatti (mtosa...@redhat.com) wrote: > > > > This patch, relative to pre-copy migratio

Re: [Qemu-devel] [QEMU PATCH v2] kvmclock: advance clock by time window between vm_stop and pre_save

2016-11-07 Thread Dr. David Alan Gilbert
* Marcelo Tosatti (mtosa...@redhat.com) wrote: > On Mon, Nov 07, 2016 at 03:46:11PM +, Dr. David Alan Gilbert wrote: > > * Marcelo Tosatti (mtosa...@redhat.com) wrote: > > > This patch, relative to pre-copy migration codepath, > > > measures the time between vm_stop() and pre_save(), > > > whic

Re: [Qemu-devel] [QEMU PATCH v2] kvmclock: advance clock by time window between vm_stop and pre_save

2016-11-07 Thread Marcelo Tosatti
On Mon, Nov 07, 2016 at 03:46:11PM +, Dr. David Alan Gilbert wrote: > * Marcelo Tosatti (mtosa...@redhat.com) wrote: > > This patch, relative to pre-copy migration codepath, > > measures the time between vm_stop() and pre_save(), > > which includes copying the remaining RAM to destination, > >

Re: [Qemu-devel] [QEMU PATCH v2] kvmclock: advance clock by time window between vm_stop and pre_save

2016-11-07 Thread Dr. David Alan Gilbert
* Marcelo Tosatti (mtosa...@redhat.com) wrote: > This patch, relative to pre-copy migration codepath, > measures the time between vm_stop() and pre_save(), > which includes copying the remaining RAM to destination, > and advances the clock by that amount. > > In a VM with 5 seconds downtime, this

Re: [Qemu-devel] [QEMU PATCH v2] kvmclock: advance clock by time window between vm_stop and pre_save

2016-11-04 Thread Juan Quintela
Marcelo Tosatti wrote: > This patch, relative to pre-copy migration codepath, > measures the time between vm_stop() and pre_save(), > which includes copying the remaining RAM to destination, > and advances the clock by that amount. > > In a VM with 5 seconds downtime, this reduces the guest > cloc

[Qemu-devel] [QEMU PATCH v2] kvmclock: advance clock by time window between vm_stop and pre_save

2016-11-04 Thread Marcelo Tosatti
This patch, relative to pre-copy migration codepath, measures the time between vm_stop() and pre_save(), which includes copying the remaining RAM to destination, and advances the clock by that amount. In a VM with 5 seconds downtime, this reduces the guest clock difference on destination from 5s t