Re: [RFC 1/6] qapi/migration: Introduce vcpu-dirtylimit-period parameters

[Hyman Huang]

在 2022/5/18 23:05, Eric Blake 写道:
> On Tue, May 17, 2022 at 02:35:01PM +0800, huangy81@chinatelecom.cn wrote:
> > From: Hyman Huang(黄勇) <huangy81@chinatelecom.cn>
> >
> > Introduce "vcpu-dirtylimit-period" migration parameters,
> > which is used to makes dirtyrate calculation period
>
> make
>
> > configurable.
> >
> > To implement that, refactor vcpu_dirty_rate_stat_collect
> > so that period can be configured instead of hardcode.
>
> hardcoded
>
> > Meanwhile, introduce migrate_dirtylimit function to help
> > check if dirtylimit enabled during live migration, set
> > it false by default.
> >
> > Signed-off-by: Hyman Huang(黄勇) <huangy81@chinatelecom.cn>
> > ---
>
> Focusing just on UI...
>
> > +++ b/qapi/migration.json
> > @@ -760,6 +760,9 @@
> >   #                        block device name if there is one, and to their node 
> > name
> >   #                        otherwise. (Since 5.2)
> >   #
> > +# @vcpu-dirtylimit-period: Periodic time (ms) of dirtylimit during live 
> > migration.
> > +#                          Defaults to 500ms. (Since 7.0)
>
> The next release is 7.1.  You'll need to fix this and all other references.
Ok, i'll fix that in the v1.
> Do we want 'dirty-limit' instead of 'dirtylimit'?  There was a recent
> thread on how to translate QAPI to other languages that are a bit more
> insistent on MixedCase, where properly separating English words makes
> it easier to translate to the expected case.
Changing the parameter name sounds ok to me, i'm not insistent that。
> >   ##
> >   # @migrate-set-parameters:
> > @@ -1125,6 +1132,9 @@
> >   #                        block device name if there is one, and to their node 
> > name
> >   #                        otherwise. (Since 5.2)
> >   #
> > +# @vcpu-dirtylimit-period: Periodic time (ms) of dirtylimit during live 
> > migration.
> > +#                          Defaults to 500ms. (Since 7.0)
> > +#
> >   # Features:
> >   # @unstable: Member @x-checkpoint-delay is experimental.
>
> Is this feature ready for prime time, or do we want to initially name
> it x-vcpu-dirty[-]limit-period to mark it experimental?
Indeed, for this fresh new feature, finding factors affecting migration 
need more practice, marking it experimental could be much safer, i'll do 
that in v1.
>

--
Best regard

Hyman Huang(黄勇)