Subject: Re: scheduler woes on MPACPI kernel
To: Manuel Bouyer <>
From: Johnny Billquist <bqt@Update.UU.SE>
List: current-users
Date: 01/18/2005 22:53:26
On Tue, 18 Jan 2005, 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.

Huh? I didn't understand this...
Are you claiming that a finer grained lock will decrease performance? Or 
is there a serious bug in the Linux kernel?


Johnny Billquist                  || "I'm on a bus
                                   ||  on a psychedelic trip
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