Re: vacuum, performance, and MVCC

On Fri, Jun 23, 2006 at 10:24:06AM -0400, Alvaro Herrera wrote:
> Mark Woodward wrote:
> > > In case of the number of actively modified rows being in only tens or
> > > low hundreds of thousands of rows, (i.e. the modified set fits in
> > > memory) the continuous vacuum process shows up as just another backend,
> > > not really taking order of magnitude more resources. It mainly generates
> > > WAL traffic, as modified pages are already in memory/cache and are
> > > mostly synced by background writer and/or checkpoint.
> > > Of course you have to adjust vacuum_cost_* variables so as to not
> > > saturate IO.
> > These sort of solutions, IMHO, don't show how good PostgreSQL is, but show
> > where it is very lacking.
> We all know Postgres is lacking; some of us try to improve it (some with
> more success than others). People who know the current limitations but
> like the capabilities, try to find workarounds to the problems. What
> surprises me is that, if you have such a low opinion of Postgres, you
> still use it.

If everybody had good opinions, where would the development come from?

It's the parts that suck that need fixing the most... :-)

Cheers,
mark

--
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