Re: Autovacuum firing up during my manual vacuum on same table

From: "Henry C(dot)" <henka(at)cityweb(dot)co(dot)za>
To: pgsql-general(at)postgresql(dot)org
Subject: Re: Autovacuum firing up during my manual vacuum on same table
Date: 2011-04-02 17:16:39
Message-ID: 0994c2fd27ee6c7ddcb9cbbd4cfa392b.squirrel@support.metroweb.co.za
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-general


Forgot to mention: I'm using 9.0.3

> Usually a manual vacuum cancels a running autovacuum task.

Not in my case - however, the autovac does seem to be in a waiting state.

> You should find a notice about the cancelation in th logfile.
>
> > current_query | vacuum analyze
> > age | 11:46:57.245568
>
> Where is the age column from?
> It's not in pg_stat_activity.

age(now(), query_start)

>> Is one of the two processes waiting=t in pg_stat_activity?

ah, there it is. Yes, the autovac is waiting.

>> > I'm trying to vacuum the table as quickly as possible so a manual
>> > vacuum seems to be in order as my understanding (and experience)
>> > is that the autovac is a hell of a lot slower to mitigate impact
>> > on general performance.
>>
>> Tune the autovacuum settings, especially the scale factors of the
>> tables in question and the cost limit.
>> Is autovacuum_vacuum_cost_limit != -1 ?
>> This could be one reason, why manual vacuum is faster.

autovacuum_vacuum_cost_limit is on default (-1).

In response to

Browse pgsql-general by date

  From Date Subject
Next Message Henry C. 2011-04-02 17:26:56 Re: Autovacuum firing up during my manual vacuum on same table
Previous Message durumdara 2011-04-02 15:00:23 Re: How to get index columns/dir/ord informations?