Subject: Re: SMP doesn?t work the way i want.
To: Martin Husemann <martin@duskware.de>
From: John Franklin <franklin@elfie.org>
List: tech-smp
Date: 02/07/2003 16:33:09
On Fri, Feb 07, 2003 at 09:06:45AM +0100, Martin Husemann wrote:
> On Fri, Feb 07, 2003 at 08:45:43AM +0100, Patrik Hansson wrote:
> 
> > Wy can't i see both in systat ?
> 
> Because systat has not been updated for multiple CPU display yet.
> It should, I guess.
> 
> > when i recompile a kernel only one cpu gets the load, and top
> > reports 50% idle. Is tha normal ?
> 
> Yes. If the system only has one process (or more precise: thread) to run, it
> can't realy use the second CPU. But for all makefiles in the NetBSD source
> treee, you can add a "-j X" argument to make, i.e. "make -j 4", to make it
> run multiple processes (compilers) at the same time.
> 
> If you have enough memory, this works great.

Not so much for me.  I have have no end of problems with it, in
particular if something fails during the build, the build scripts skip
to the "install" phase instead of dying at the point of failure.

Sometimes this is aggravated by build race-conditions.  I have run into
them in the past, but I don't have any examples.  Typically, it
manifests as an attempt to link to a library that's not yet finished
building.  I'll give it another try this weekend and see if I can't find
some concrete examples to send-pr.

If this has been corrected, then toolchain/18573 should be closed.

jf
-- 
John Franklin
franklin@elfie.org
ICBM: 35°43'56"N 78°53'27"W