> We have postgres running on freebsd 4.9 with 2 Gigs of memory. As per
> repeated advice on the mailing lists we configured effective_cache_size
> = 25520 which you get by doing `sysctl -n vfs.hibufspace` / 8192
>
> Which results in using 200Megs for disk caching.
effective_cache_size does nothing of the sort. CHeck your
shared_buffers value...
> Is there a reason not to increase the hibufspace beyond the 200 megs and
> provide a bigger cache to postgres? I looked both on the postgres and
> freebsd mailing lists and couldn't find a good answer to this.
Well, maybe butnot necessarily. It's better to leave the OS to look after
most of your RAM.
Chris