Re: free space map usage - Mailing list pgsql-performance

From Jeremy M. Guthrie
Subject Re: free space map usage
Date
Msg-id 200310141447.05788.jeremy.guthrie@berbee.com
Whole thread Raw
In response to Re: free space map usage  (Tom Lane <tgl@sss.pgh.pa.us>)
Responses Re: free space map usage
List pgsql-performance
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On Tuesday 14 October 2003 02:16 pm, Tom Lane wrote:
> "Jeremy M. Guthrie" <jeremy.guthrie@berbee.com> writes:
> > Is there any way to determine how much of the free space map is currently
> > i= n=20
> > use?(ie. where and what it is tracking?)  I vacuum on a regular basis but
> > I= =20
> > never hold in terms of disk space usage.
>
> Not in 7.3 AFAIR.  In 7.4 a full-database VACUUM VERBOSE will end with
> the info you want:
>
> regression=# vacuum verbose;
> ... much cruft ...
> INFO:  free space map: 11 relations, 144 pages stored; 272 total pages
> needed DETAIL:  Allocated FSM size: 1000 relations + 20000 pages = 178 kB
> shared memory. VACUUM
> regression=#
>
> This tells me I'm only using about 1% of the FSM space (272 out of 20000
> page slots).
>
> > I jacked up the free space map=20
> > pages but this doesn't appear to be working.
>
> You know you have to restart the postmaster to make those changes take
> effect, right?
Yup.  I still see no effect after restart.

>             regards, tom lane

- --
Jeremy M. Guthrie
Systems Engineer
Berbee
5520 Research Park Dr.
Madison, WI  53711
Phone:  608-298-1061

Berbee...Decade 1.  1993-2003
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