Re: Manual vacs 5x faster than autovacs?

On Thu, Nov 12, 2009 at 7:33 AM, Wayne Beaver <wayne@acedsl.com> wrote:
> Hi All,
>
> Running Pg 8.3RC2, Linux server, w/8GB RAM, OpenSuSE 10.2 OS (yes, I know
> that's old). I have seen *really* long-running autovacs eating up system
> resources. While the below is not an example of *really* long, it shows how
> I killed an autovac which had been running for more than 10 minutes, then
> ran a VAC FULL ANALYZE on same exact table in about ~2 min. Any wisdom here?
> Attributable to autovac_worker settings? Or Pg version? Other?
>
> Any insight appreciated.

Autovac running slow is (generally) a good thing.  It reduces the load
on your IO subsystem so that other queries can still run fast.  What
resources are your long running autovacs eating up.  If top shows
500Mres and 499Mshr, then don't worry, it's not actually eating up
resources.