Re: [PATCH 0/3] Optimize VM's downtime while do checkpoint in COLO

["Dr. David Alan Gilbert" <dgilbert@redhat.com>]

* Hailiang Zhang (zhang.zhanghailiang@huawei.com) wrote:
> Hi,
> 
> This is an untested serial that tries to reduce VM's pause time
> while do checkpoint in COLO state.
> 
> The second patch tries to reduce the total number of dirty pages
> while do checkpoint with VM been paused, instead of sending all
> dirty pages while VM been pause, it sends part of dirty pages during
> the gap time of two checkpoints when SVM and PVM are running.
> 
> The third patch tries to reduce the pause time of backup ram into
> cache in secondary part.

This is quite nice; I've asked for a clarification on the last one, but
it's only a tidy up.

I guess this really helps continuous-COLO as well, because it means
that restarting to the sync to the new secondary is a lot simpler?

Dave

> 
> Hailiang Zhang (3):
>   migration/colo: wrap incoming checkpoint process into new helper
>   COLO: Migrate dirty pages during the gap of checkpointing
>   COLO: Optimize memory back-up process
> 
>  migration/colo.c       | 332 +++++++++++++++++++++++++----------------
>  migration/migration.h  |   1 +
>  migration/ram.c        |  35 ++++-
>  migration/ram.h        |   1 +
>  migration/trace-events |   1 +
>  qapi/migration.json    |   4 +-
>  6 files changed, 234 insertions(+), 140 deletions(-)
> 
> -- 
> 2.21.0
> 
> 
--
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK