Subject: Re: scheduler woes on MPACPI kernel
To: None <current-users@NetBSD.org>
From: None <sigsegv@rambler.ru>
List: current-users
Date: 01/18/2005 20:25:51
Manuel Bouyer wrote:
> On Tue, Jan 18, 2005 at 05:09:48PM +0200, Teemu Rinta-aho wrote:
> 
>>Does anyone know if there has been any analysis on the
>>effect of P4 hyperthreading and MP support of NetBSD,
>>compared to a UP kernel?
> 
> 
> I tested with a make -j4 kernel build. A few % improvements with a MP kernel.
> But this is because we have a big kernel lock I think. On linux 2.6, which
> has finer-grained locking, a MP kernel increased the build time instead of
> decreasing it.
> 

So there is no point in having MP system if it actually increases total 
time :-)
Somebody did a benchmark recently of NetBSD vs FreeBSD and NetBSD came 
on top. So people said if it was done on a MP system, FreeBSD would be 
faster, due to finer-grained locking, etc. Any ideas if that's true?