Re: [Qemu-devel] [PATCH] migration: always initial ram_counters for a new migration

[Ivan Ren]

On Fri, Aug 2, 2019 at 1:59 PM Wei Yang <address@hidden> wrote:
>
> On Fri, Aug 02, 2019 at 01:46:41PM +0800, Ivan Ren wrote:
> >>>>>     s->iteration_start_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME);
> >>>>>+    /*
> >>>>>+     * Update s->iteration_initial_bytes to match
> >>>s->iteration_start_time.
> >>>>>+     */
> >>>>>+    s->iteration_initial_bytes = migration_total_bytes(s);
> >>>>
> >>>>Is this one necessary? We have sent out nothing yet.
> >>>
> >>>Yes, currently nothing has been sent yet at this point.
> >>>
> >>>Is that better to always match the update of iteration_initial_bytes
> >>>and iteration_start_time in a explicit way to avoid some potential
> >missing?
> >>>
> >>
> >>You may get some point. Well after a close look, we may find other
> >potential
> >>problem.
> >>
>
> Well, I guess you need to use another tool to send mail. The format is
> corrupted.
>

OK

> >>1. To be consistency, we need to update iteration_initial_pages too.
> >>   So my opinion is to wrap the update of these three counters into a
> >helper
> >>   function. So each time all of them.
>
> I don't see you reply this one or the mail is corrupted.
>
> If we don't update iteration_initial_pages, the initial_pages will mismatch
> the initial_bytes. Am I right?

Yes, agree, I'll send a new version, thanks.

>
> >>2. In function ram_get_total_transferred_pages, do we missed multifd_bytes?
> >
> >In function ram_save_multifd_page, ram pages transferred by multifd threads
> >is
> >counted by ram_counters.normal.
> >You mean other multifd bytes like multifd packet or multifd sync info?
> >
>
> Ok, it is counted in normal.
>
> While if my understanding is correct, normal is used to count pages sent by
> save_normal_page(). Sounds this is misused?
>

Yes, current it is counted in normal, a  specific counter is more accurate.

Thanks