Thread: Vacuum v/s Autovacuum

Vacuum v/s Autovacuum

From
"Gauri Kanekar"
Date:
Hi List,
 
Can anybody help me out with this -
 
is autovacuum similar to vacuum full analyse verbose.
 
--
Regards
Gauri

Re: Vacuum v/s Autovacuum

From
Michael Glaesemann
Date:
On Jan 18, 2007, at 22:24 , Gauri Kanekar wrote:

> is autovacuum similar to vacuum full analyse verbose.

http://www.postgresql.org/docs/8.2/interactive/routine-
vacuuming.html#AUTOVACUUM

Apparently, no FULL, no VERBOSE (which is only really useful if you
want to see the results, not for routine maintenance).


Michael Glaesemann
grzm seespotcode net



Re: Vacuum v/s Autovacuum

From
"Gauri Kanekar"
Date:
Hi
 
Thanks.
 
We have autovacuum ON , but still postgres server warns to increas max_fsm_pages value.
 
Do autovacuum release space after it is over?
 
so how can we tackle it.
 


 
On 1/18/07, Michael Glaesemann <grzm@seespotcode.net> wrote:

On Jan 18, 2007, at 22:24 , Gauri Kanekar wrote:

> is autovacuum similar to vacuum full analyse verbose.

http://www.postgresql.org/docs/8.2/interactive/routine-
vacuuming.html#AUTOVACUUM

Apparently, no FULL, no VERBOSE (which is only really useful if you
want to see the results, not for routine maintenance).


Michael Glaesemann
grzm seespotcode net





--
Regards
Gauri

Re: Vacuum v/s Autovacuum

From
Bill Moran
Date:
In response to "Gauri Kanekar" <meetgaurikanekar@gmail.com>:
> On 1/18/07, Michael Glaesemann <grzm@seespotcode.net> wrote:
> >
> > On Jan 18, 2007, at 22:24 , Gauri Kanekar wrote:
> >
> > > is autovacuum similar to vacuum full analyse verbose.
> >
> > http://www.postgresql.org/docs/8.2/interactive/routine-
> > vacuuming.html#AUTOVACUUM
> >
> > Apparently, no FULL, no VERBOSE (which is only really useful if you
> > want to see the results, not for routine maintenance).

[please don't top-post]

Actually, you can raise the debugging level in PostgreSQL and get something
similar to VERBOSE.  The only problem is that it also increases the amount
of logging that occurs with everything.

> We have autovacuum ON , but still postgres server warns to
> increas max_fsm_pages value.
>
> Do autovacuum release space after it is over?

Yes.

If you're still getting warnings about max_fsm_pages while autovac is
running, you need to do one of two things:
1) Increase max_fsm_pages
2) Adjust autovacuum's settings so it vacuums more often.

Depending on this, you may also need to temporarily adjust max_fsm_pages,
then manually vacuum -- you may then find that autovacuum can keep everything
clean with lower settings of max_fsm_pages.

Overall, the best settings for 1 and 2 depend on the nature of your
workload, and simulation and monitoring will be required to find the
best values.  I feel that the docs on this are very good.  If the
amount of data that changes between runs of autovacuum is greater
than max_fsm_pages, then vacuum will be unable to reclaim all the
space.

--
Bill Moran
Collaborative Fusion Inc.

Re: Vacuum v/s Autovacuum

From
"Shoaib Mir"
Date:
You will need to properly tune the thresholds for VACUUM and ANALYZE in case of autovacuuming process, so that you do not need to increase the max_fsm_pages oftenly...

-------------
Shoaib Mir
EnterpriseDB ( www.enterprisedb.com)

On 1/18/07, Bill Moran <wmoran@collaborativefusion.com> wrote:
In response to "Gauri Kanekar" <meetgaurikanekar@gmail.com >:
> On 1/18/07, Michael Glaesemann <grzm@seespotcode.net> wrote:
> >
> > On Jan 18, 2007, at 22:24 , Gauri Kanekar wrote:
> >
> > > is autovacuum similar to vacuum full analyse verbose.
> >
> > http://www.postgresql.org/docs/8.2/interactive/routine-
> > vacuuming.html#AUTOVACUUM
> >
> > Apparently, no FULL, no VERBOSE (which is only really useful if you
> > want to see the results, not for routine maintenance).

[please don't top-post]

Actually, you can raise the debugging level in PostgreSQL and get something
similar to VERBOSE.  The only problem is that it also increases the amount
of logging that occurs with everything.

> We have autovacuum ON , but still postgres server warns to
> increas max_fsm_pages value.
>
> Do autovacuum release space after it is over?

Yes.

If you're still getting warnings about max_fsm_pages while autovac is
running, you need to do one of two things:
1) Increase max_fsm_pages
2) Adjust autovacuum's settings so it vacuums more often.

Depending on this, you may also need to temporarily adjust max_fsm_pages,
then manually vacuum -- you may then find that autovacuum can keep everything
clean with lower settings of max_fsm_pages.

Overall, the best settings for 1 and 2 depend on the nature of your
workload, and simulation and monitoring will be required to find the
best values.  I feel that the docs on this are very good.  If the
amount of data that changes between runs of autovacuum is greater
than max_fsm_pages, then vacuum will be unable to reclaim all the
space.

--
Bill Moran
Collaborative Fusion Inc.

---------------------------(end of broadcast)---------------------------
TIP 2: Don't 'kill -9' the postmaster