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To: Steve Passe <smp@csn.net>
cc: NISHIO Shuichi <nishio@caleche.kecl.ntt.co.jp>, freebsd-smp@freebsd.org
Subject: Re: Tyan ATX1668 problem -- success 
In-reply-to: Your message of "Fri, 25 Apr 1997 09:18:41 CST."
             <199704251518.JAA07978@Ilsa.StevesCafe.com> 
Date: Fri, 25 Apr 1997 23:47:06 +0800
From: Peter Wemm <peter@spinner.dialix.com>
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Steve Passe wrote:
> As to the improved performance, this is because we are taking a big hit on
> all those TLB invalidations (has to be done), and the old method was competin
    g
> for the kernel lock each time.  The new method goes right for it without the
> lock.

No.. The old method wasn't fetching the kernel lock either..  I suspect 
that the speedup was because the old method was using the generic 
IPI_INTR() handler which was set up for calling C code, while the new one 
is a cut down version that doesn't have as much overhead.  (Incidently, 
the new one doesn't show up on the vmstat interrupt counts)

Cheers,
-Peter