Re: Server vacuuming the same table again and again

Hi Ilya!

> Actually, thise two things are tightly bound and there is no chance to avoid
vacuum, you can only postpone it, this kind of work eventually supposed to
be done.

I understand that autovacuum has to be done, but not right after previous
autovacuum? And then again and again.
And after cancelling that first autovacuum I started another one by hand;
from there no autovacuum was cancelled.

> ionice autovacuum instead of mission critical ckeckpointer or bgwriter
Yeah, that was desperate. I restarted server when I had a chance - to drop
my ionice settings back to defaults.

> Which exact values have you in the following settings:

autovacuum_analyze_scale_factor = 0.1
autovacuum_analyze_threshold = 50
autovacuum_freeze_max_age = 200000000
autovacuum_max_workers = 3
autovacuum_naptime = 60
autovacuum_vacuum_cost_delay = 20
autovacuum_vacuum_cost_limit = -1
autovacuum_vacuum_scale_factor = 0.2
autovacuum_vacuum_threshold = 50
log_autovacuum_min_duration = 0

All defaults except last one I believe.

Minwhile I noticed in the night logs:
checkpoints are occurring too frequently (138 seconds apart)
Consider increasing the configuration parameter "checkpoint_segments".

Increased checkpoint_segments to 256 and reloaded config.

Best regards,
Dmitriy Shalashov

2014-04-25 12:12 GMT+04:00 Ilya Kosmodemiansky <
ilya(dot)kosmodemiansky(at)postgresql-consulting(dot)com>:

> Hi Dmitry,
>
> On Fri, Apr 25, 2014 at 9:47 AM, Дмитрий Шалашов <skaurus(at)gmail(dot)com>
> wrote:
> > cancelled autovacuum and it seems to help.
>
> > In the morning autovacuum was back. And then it finished and I gone to
> work.
>
> Actually, thise two things are tightly bound and there is no chance to
> avoid vacuum, you can only postpone it, this kind of work eventually
> supposed to be done.
>
> What you really need to do as a first thing - configure your
> autovacuum aggressively enough and then mayde ionice autovacuum
> instead of mission critical ckeckpointer or bgwriter.
>
> Which exact values have you in the following settings:
>
> autovacuum_analyze_scale_factor
> autovacuum_analyze_threshold
> autovacuum_freeze_max_age
> autovacuum_max_workers
> autovacuum_naptime
> autovacuum_vacuum_cost_delay
> autovacuum_vacuum_cost_limit
> autovacuum_vacuum_scale_factor
> autovacuum_vacuum_threshold
> log_autovacuum_min_duration
>
> ?
>
> Best regards, Ilya
> >
> > Best regards,
> > Dmitriy Shalashov
>
>
>
> --
> Ilya Kosmodemiansky,
>
> PostgreSQL-Consulting.com
> tel. +14084142500
> cell. +4915144336040
> ik(at)postgresql-consulting(dot)com
>