Re: increasing max_fsm_pages.

On Mon, May 15, 2006 at 12:18:50PM +0530, Gourish Singbal wrote:
> Group.
>
> Need some help in understanding the tuning parameter.
>
> we got the below message on database wide vacuuming :-
> Vacuuming Result outcome on Sun May 14 20:22:47 PDT 2006 :-
> INFO: free space map contains 195236 pages in 72 relations
> DETAIL: A total of 200000 page slots are in use (including overhead).
> 201744 page slots are required to track all free space.
> Current limits are: 200000 page slots, 500 relations, using 1226 KB.
> NOTICE: number of page slots needed (201744) exceeds max_fsm_pages (200000)
> HINT: Consider increasing the configuration parameter "max_fsm_pages" to a
> value over 201744.
> VACUUM
>
> We have 4 GB of RAM on the machine if we increase the max_fsm_pages to
> 300000 will the database performance be at stake ?.

I'd say more accurately it'll be at stake if you don't. Each page slot
takes 6 bytes, so you'll be using an additional 600k, which is
essentially nothing.

This article was written using the older vacuum output, but it might
still be informative for you:
http://www.pervasivepostgres.com/lp/newsletters/2005/Insights_opensource_Nov.asp#3
--
Jim C. Nasby, Sr. Engineering Consultant jnasby(at)pervasive(dot)com
Pervasive Software http://pervasive.com work: 512-231-6117
vcard: http://jim.nasby.net/pervasive.vcf cell: 512-569-9461