Re: [PATCH 01/16] Overhaul walsender wakeup handling

On Fri, Jun 22, 2012 at 10:45 AM, Andres Freund <andres(at)2ndquadrant(dot)com> wrote:
>> > the likelihood of that as you know.
>> Hmm, well, I guess.  I'm still not sure I really understand what
>> benefit we're getting out of this.  If we lose a few WAL records for
>> an uncommitted transaction, who cares?  That transaction is gone
>> anyway.
> Well, before the simple fix Simon applied after my initial complaint you
> didn't get wakeups *at all* in the synchronous_commit=off case.
>
> Now, with the additional changes, the walsender is woken exactly when data is
> available to send and not always when a commit happens. I played around with
> various scenarios and it always was a win.

Can you elaborate on that a bit? What scenarios did you play around
with, and what does "win" mean in this context?

--
Robert Haas
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