Subject: Re: Configuring memory parameters for large network-based services
To: None <email@example.com>
From: I. Souvatzis <firstname.lastname@example.org>
Date: 03/23/1999 11:36:49
On Mon, Mar 22, 1999 at 05:07:00PM -0800, Jason Thorpe wrote:
> On Mon, 22 Mar 1999 12:48:21 -0800
> Jason Thorpe <email@example.com> wrote:
> > > That is, what units is this in? I'm guessing 2048 (cluster size)
> > > bytes.
> > No, "clusters" in this sense is the historic "page cluster", i.e.
> > VM page size (as opposed to hardware page size :-) In the NetBSD
> > kernel, CLBYTES == PAGE_SIZE :-)
> > Confusing enough yet? :-)
> > So, on i386, 4k. On Alpha, 8k. On SPARC, 8k. Etc.
> BTW, after reexamination of the code, NMBCLUSTERS does in fact mean
> "number of mbuf clusters", not "number of VM pages in map". I have
> clarified this in options(4), and fixed the ports which defined it
> incorrectly (the PowerPC ports).
Side note: the UVM thesis says that if it is upped to the VM page size,
network drivers could be changed to benefit from page loadout etc.
But I guess THIS is nothing which will be done in time for 1.4.