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From: Andrew Gallatin <gallatin@cs.duke.edu>
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Date: Thu, 1 Feb 2007 14:46:13 -0500 (EST)
To: Julian Elischer <julian@elischer.org>
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Cc: FreeBSD Current <current@freebsd.org>
Subject: Re: lock contention etc.
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Julian Elischer writes:
 > I'm guessing that the extra system time represents a lot of
 > contention somewhere.
 > 
 > What is the best way to get actual numbers on this?

The Dtrace lockstat tool is designed for this, and I've used it to
track down contention like this on Solaris.  It seems to be on the
TODO list for the FreeBSD Dtrace port at
http://people.freebsd.org/~jb/dtrace/todo.html.  I wonder how soon it
will arrive..  It is one of the things that I'm most looking forward
to.

Drew