Re: [HACKERS] Autovacuum Improvements

On Fri, Jan 12, 2007 at 07:33:05PM -0300, Alvaro Herrera wrote:
> Simon Riggs wrote:
>
> > Some feedback from initial testing is that 2 queues probably isn't
> > enough. If you have tables with 100s of blocks and tables with millions
> > of blocks, the tables in the mid-range still lose out. So I'm thinking
> > that a design with 3 queues based upon size ranges, plus the idea that
> > when a queue is empty it will scan for tables slightly above/below its
> > normal range.
>
> Yeah, eventually it occurred to me the fact that as soon as you have 2
> queues, you may as well want to have 3 or in fact any number. Which in
> my proposal is very easily achieved.
>
>
> > Alvaro, have you completed your design?
>
> No, I haven't, and the part that's missing is precisely the queues
> stuff. I think I've been delaying posting it for too long, and that is
> harmful because it makes other people waste time thinking on issues that
> I may already have resolved, and delays the bashing that yet others will
> surely inflict on my proposal, which is never a good thing ;-) So maybe
> I'll put in a stub about the "queues" stuff and see how people like the
> whole thing.

Have you made any consideration of providing feedback on autovacuum to users?
Right now we don't even know what tables were vacuumed when and what was
reaped. This might actually be another topic.

---elein
elein(at)varlena(dot)com