Re: is pg_autovacuum so effective ?

From: "Matthew T(dot) O'Connor" <matthew(at)zeut(dot)net>
To: Gaetano Mendola <mendola(at)bigfoot(dot)com>
Cc: pgsql-performance(at)postgresql(dot)org
Subject: Re: is pg_autovacuum so effective ?
Date: 2005-02-22 20:58:01
Message-ID: 421B9CD9.6090703@zeut.net
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-performance

Gaetano Mendola wrote:

>pg_class after the vacuum full for that table
>
> relfilenode | relname | relpages | reltuples
>-------------+----------+----------+-------------
> 18376 | messages | 63307 | 1.60644e+06
>
>
>pg_class before the vacuum full for that table
>
> relfilenode | relname | relpages | reltuples
>-------------+----------+----------+-------------
> 18376 | messages | 69472 | 1.60644e+06
>
>
>
>how was possible accumulate 6000 pages wasted on that table?
>
>Between these two calls:
>[2005-02-22 05:25:03 CET] Performing: VACUUM ANALYZE "public"."messages"
>[2005-02-22 15:20:39 CET] Performing: VACUUM ANALYZE "public"."messages"
>
>1768 rows where inserted, and I had 21578 updated for that rows ( each
>row have a counter incremented for each update ) so that table is not
>so heavy updated
>
>I'm running autovacuum with these parameters:
>pg_autovacuum -d 3 -v 300 -V 0.1 -S 0.8 -a 200 -A 0.1 -D
>
>
>shall I run it in a more aggressive way ? May be I'm missing
>something.
>

Well without thinking too much, I would first ask about your FSM
settings? If they aren't big enought that will cause bloat. Try
bumping your FSM settings and then see if you reach steady state.

In response to

Responses

Browse pgsql-performance by date

  From Date Subject
Next Message Tom Lane 2005-02-22 21:28:03 Re: is pg_autovacuum so effective ?
Previous Message Mark Kirkwood 2005-02-22 20:07:16 Re: Problem with 7.4.5 and webmin 1.8 in grant function