From owner-freebsd-current  Tue Jul 13  8:55:31 1999
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Date: Tue, 13 Jul 1999 08:55:28 -0700 (PDT)
From: Matthew Dillon <dillon@apollo.backplane.com>
Message-Id: <199907131555.IAA78738@apollo.backplane.com>
To: "Brian F. Feldman" <green@FreeBSD.org>
Cc: Peter Jeremy <jeremyp@gsmx07.alcatel.com.au>,
	freebsd-current@FreeBSD.org
Subject: Re: LOCK overheads (was Re: "objtrm" problem probably found)
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:Here's another data point:
:{"/home/green"}$ cc -O2 locktests.c -o locktests
:{"/home/green"}$ ./locktests
:mode 0   10.92 ns/loop nproc=1 lcks=EMPTY
:mode 1   17.99 ns/loop nproc=1 lcks=no
:mode 2   17.97 ns/loop nproc=2 lcks=no
:mode 3  166.33 ns/loop nproc=1 lcks=yes
:mode 4  167.91 ns/loop nproc=2 lcks=yes
:mode 5   42.16 ns/loop nproc=1 lcks=no
:mode 6   41.60 ns/loop nproc=2 lcks=no
:mode 7  188.86 ns/loop nproc=1 lcks=yes
:mode 8  191.56 ns/loop nproc=2 lcks=yes
:
:This is a K6-2 350. Locks are pretty expensive on them.
:
: Brian Fundakowski Feldman      _ __ ___ ____  ___ ___ ___  

    Wow, now that *is* expensive!  The K6 must be implementing it in
    microcode for it to be that bad.

					-Matt
					Matthew Dillon 
					<dillon@backplane.com>


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