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Date: Tue, 16 Mar 2004 13:32:10 -0800 (PST)
From: Doug White <dwhite@gumbysoft.com>
To: Seigo Tanimura <tanimura@tanimura.dyndns.org>
In-Reply-To: <200403160519.i2G5J0V6023193@urban>
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References: <200403160519.i2G5J0V6023193@urban>
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cc: arch@FreeBSD.org
Subject: Re: Is MTX_CONTESTED evil?
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On Tue, 16 Mar 2004, Seigo Tanimura wrote:

> What would it be like if we axed MTX_CONTEST and let
> _mtx_unlock_sleep() wake up all of the blocked threads?

Excuse my naievete, but this sounds like it would trigger a
thundering-herd response on a heavily contested mutex (like Giant).  That
would be Bad. :)

-- 
Doug White                    |  FreeBSD: The Power to Serve
dwhite@gumbysoft.com          |  www.FreeBSD.org