Re: stats collector suddenly causing lots of IO

Josh Kupershmidt wrote:
> And it seems the only way
> to compact the pg_catalog tables is VACUUM FULL + REINDEX on 8.3 -- I
> had tried the CLUSTER on my 9.0 machine and wrongly assumed it would
> work on 8.3, too.
>

Right; that just got implemented a couple of months ago.  See the news
from http://www.postgresql.org/community/weeklynews/pwn20100214 for a
summary of how the code was gyrated around to support that.  This is a
tough situation to get out of in <9.0 because VACUUM FULL is slow and
takes an exclusive lock on the table.  That tends to lead toward an
unpredictable window for required downtime, which is never good.

--
Greg Smith  2ndQuadrant US  Baltimore, MD
PostgreSQL Training, Services and Support
greg@2ndQuadrant.com   www.2ndQuadrant.us