Re: [Testperf-general] pg_autovacuum w/ dbt2

On Fri, Jan 07, 2005 at 09:58:47AM -0800, Josh Berkus wrote:
> Mark,
> 
> > No manual vacuum commands before.  The decline in performance has been
> > pretty consistent in all my previous tests and people have told me on
> > many occasions that the decline in performance was probably because I
> > was never using vacuum...
> 
> Hmmm ... what autovacuum params are you using?  From the look of the graphs, 
> VACUUM is running every 6 minutes or so, and having a huge impact on 
> performance when it does run.  Give me a bit of time to crunch the database 
> log, and we'll see which table vacuums were taking the most time.
> 
> Can you re-run this test with a fairly generous vacuum_delay setting? Given 
> that the performance drops seem to correspond to wait times, I think this 
> could mean a big difference.
> 

All default parameters.  Matthew also recommended using the
vacuum_delay setting so I was about to try that.

Mark