Re: Best OS & Configuration for Dual Xeon w/4GB &

On Mon, 2006-03-20 at 08:45, Jim C. Nasby wrote:
> On Fri, Mar 17, 2006 at 05:00:34PM -0600, Scott Marlowe wrote:
> > > last pid: 5788; load averages: 0.32, 0.31, 0.28 up 127+15:16:08 13:59:24
> > > 169 processes: 1 running, 168 sleeping
> > > CPU states: 5.4% user, 0.0% nice, 9.9% system, 0.0% interrupt, 84.7% idle
> > > Mem: 181M Active, 2632M Inact, 329M Wired, 179M Cache, 199M Buf, 81M Free
> > > Swap: 4096M Total, 216K Used, 4096M Free
> > >
> > > PID USERNAME PRI NICE SIZE RES STATE C TIME WCPU CPU COMMAND
> > > 14501 pgsql 2 0 254M 242M select 2 76:26 1.95% 1.95% postgre
> > > 5720 root 28 0 2164K 1360K CPU0 0 0:00 1.84% 0.88% top
> > > 5785 pgsql 2 0 255M 29296K sbwait 0 0:00 3.00% 0.15% postgre
> > > 5782 pgsql 2 0 255M 11900K sbwait 0 0:00 3.00% 0.15% postgre
> > > 5772 pgsql 2 0 255M 11708K sbwait 2 0:00 1.54% 0.15% postgre
> >
> > That doesn't look good. Is this machine freshly rebooted, or has it
> > been running postgres for a while? 179M cache and 199M buffer with 2.6
> > gig inactive is horrible for a machine running a 10gig databases.
>
> No, this is perfectly fine. Inactive memory in FreeBSD isn't the same as
> Free. It's the same as 'active' memory except that it's pages that
> haven't been accessed in X amount of time (between 100 and 200 ms, I
> think). When free memory starts getting low, FBSD will start moving
> pages from the inactive queue to the free queue (possibly resulting in
> writes to disk along the way).
>
> IIRC, Cache is the directory cache, and Buf is disk buffers, which is
> somewhat akin to shared_buffers in PostgreSQL.

So, then, the inact is pretty much the same as kernel buffers in linux?