Thanks for the pointer. So
maxbufspace = nbuf * BKVASIZE;
Which is confirmed in
http://unix.derkeiler.com/Mailing-Lists/FreeBSD/performance/2003-09/0045.html
and it looks like there's a patch by Sean Chittenden at
http://people.freebsd.org/~seanc/patches/patch-HEAD-kern.nbuf
that does what I was asking. Seems a little on the bleeding edge. Has
anyone tried this?
On Thu, Feb 26, 2004 at 04:36:01PM -0600, Kevin Barnard wrote:
> On 26 Feb 2004 at 13:58, Dror Matalon wrote:
>
> >
> > which brings me back to my question why not make Freebsd use more of its
> > memory for disk caching and then tell postgres about it.
> >
>
> I think there is some confusion about maxbufsize and hibufspace. I looking at a
> comment in the FreeBSB source 4.9 that explains this. I think you will want to
> increase effective_cache to match maxbufsize not hibufspace but I could be wrong.
>
> $FreeBSD: src/sys/kern/vfs_bio.c,v 1.242.2.21 line 363
>
--
Dror Matalon
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