Re: VACUUM not doing its job?

Kristian Eide wrote:
> Thanks, very helpful, although there does not seem to be much description of
> what the two free space map options in postgresql.conf actually do. Doing a
> VACUUM ANALYZE VERBOSE on my largest table gives me:
> 
> NOTICE:  Pages 43681: Changed 208, Empty 0; Tup 1921387: Vac 61669, Keep 0,
> UnUsed 1362341.
> 
> I will try to increase the 'max_fsm_pages' option from 10000 to 500000 and
> see if that helps.
> 

Note that you'll need to do a vacuum full *first* to recover the lost 
space, since the free space map is populated as the tuples are actually 
freed, I believe. After that you can adjust 'max_fsm_pages' and your 
vacuum frequency to achieve an equilibrium.

Joe