Re: First steps with 8.3 and autovacuum launcher

On Thu, 2007-10-04 at 14:33 -0400, Alvaro Herrera wrote:
> Tom Lane escribió:
> > Alvaro Herrera <alvherre(at)commandprompt(dot)com> writes:
> > > Gregory Stark escribi:
> > >> A crazy idea I just had -- what if you roll this into the deadlock check? So
> > >> after waiting on the lock for 1s it wakes up, finds that the holder it's
> > >> waiting on is an autovacuum process and cancels it instead of finding no
> > >> deadlock.
> >
> > > Another crazy idea is to have some sort of "blacklist" of tables in
> > > shared memory. Any autovacuum process would skip those tables.
> >
> > The deadlock check idea sounds promising to me, not least because it
> > avoids adding any cycles in performance-critical paths. I'm not certain
> > how easy it'd be to fold the idea into the checker though. That
> > logic is pretty complicated :-( and I'm not sure that it makes a
> > consistent effort to visit every possible blocker.
>
> The idea sounds interesting, but I am not at all sure how to fit it in
> the deadlock code.
>
> I am totally uninclined to mess with this stuff.

I'll look at it, if Greg isn't already doing so.

--
Simon Riggs
2ndQuadrant http://www.2ndQuadrant.com