Re: [External] Re: [PATCH v4 2/7] migration/multifd: Implement zero page transmission on the multifd thread.

From: Hao Xiang <hao.xiang@bytedance.com>
To: Markus Armbruster <armbru@redhat.com>
Cc: pbonzini@redhat.com, berrange@redhat.com, eduardo@habkost.net,
	 peterx@redhat.com, farosas@suse.de, eblake@redhat.com,
	thuth@redhat.com,  lvivier@redhat.com, jdenemar@redhat.com,
	marcel.apfelbaum@gmail.com,  philmd@linaro.org,
	wangyanan55@huawei.com, qemu-devel@nongnu.org
Subject: Re: [External] Re: [PATCH v4 2/7] migration/multifd: Implement zero page transmission on the multifd thread.
Date: Fri, 1 Mar 2024 14:49:40 -0800	[thread overview]
Message-ID: <CAAYibXhbeC3GJVghkgnzrFCJT1veNs1UkGJ4Sxih_ALqV9LQog@mail.gmail.com> (raw)
In-Reply-To: <871q8uqule.fsf@pond.sub.org>

On Thu, Feb 29, 2024 at 11:28 PM Markus Armbruster <armbru@redhat.com> wrote:
>
> Hao Xiang <hao.xiang@bytedance.com> writes:
>
> > 1. Add zero_pages field in MultiFDPacket_t.
> > 2. Implements the zero page detection and handling on the multifd
> > threads for non-compression, zlib and zstd compression backends.
> > 3. Added a new value 'multifd' in ZeroPageDetection enumeration.
> > 4. Handle migration QEMU9.0 -> QEMU8.2 compatibility.
> > 5. Adds zero page counters and updates multifd send/receive tracing
> > format to track the newly added counters.
> >
> > Signed-off-by: Hao Xiang <hao.xiang@bytedance.com>
>
> [...]
>
> > diff --git a/qapi/migration.json b/qapi/migration.json
> > index 8da05dba47..846d0411d5 100644
> > --- a/qapi/migration.json
> > +++ b/qapi/migration.json
> > @@ -671,10 +671,15 @@
> >  #
> >  # @legacy: Perform zero page checking in main migration thread.
> >  #
> > +# @multifd: Perform zero page checking in multifd sender thread.
> > +#     This option only takes effect if migration capability multifd
> > +#     is set.  Otherwise, it will have the same effect as legacy.
>
> Suggest
>
>    # @multifd: Perform zero page checking in multifd sender thread if
>    #     multifd migration is enabled, else in the main migration
>    #     thread as for @legacy.
>
> Thoughts?

Sounds good. Will change that.

>
> > +#
> >  # Since: 9.0
> > +#
> >  ##
> >  { 'enum': 'ZeroPageDetection',
> > -  'data': [ 'none', 'legacy' ] }
> > +  'data': [ 'none', 'legacy', 'multifd' ] }
> >
> >  ##
> >  # @BitmapMigrationBitmapAliasTransform:
>
> QAPI schema
> Acked-by: Markus Armbruster <armbru@redhat.com>
>