From owner-freebsd-hackers  Fri Jun 11 23:15:18 1999
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	Fri, 11 Jun 1999 23:15:15 -0700
To: "David E. Cross" <crossd@cs.rpi.edu>
Cc: freebsd-hackers@FreeBSD.ORG
Subject: Re: High syscall overhead?
References: <199906111440.KAA70517@cs.rpi.edu>
From: Arun Sharma <adsharma@home.com>
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"David E. Cross" <crossd@cs.rpi.edu> writes:

> Looking through the exception.s it appears that on entry to the
> kernel an MP lock is obtained...  I thought we had splX(); to
> protect concurancy in the kernel.

Can someone explain to me why is SYSCALL_LOCK necessary ? It certainly
seems to hurt system call performance on a MP machine.

Also, is there any data on lock contention in FreeBSD ? Is anyone
working on decomposing some of the giant locks ?

	-Arun


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