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To: Robert Watson <rwatson@FreeBSD.org>
References: <Pine.NEB.3.96L.1040131234955.17012E-100000@fledge.watson.org>
From: des@des.no (Dag-Erling =?iso-8859-1?q?Sm=F8rgrav?=)
Date: Sun, 01 Feb 2004 06:12:28 +0100
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	(Robert Watson's message of "Sun, 1 Feb 2004 00:01:07 -0500 (EST)")
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cc: current@FreeBSD.org
Subject: Re: Coalescing pipe allocation
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Robert Watson <rwatson@FreeBSD.org> writes:
> FYI, the vast majority of the cost of pipe creation appears to be in
> setting up those mappings.  I ran some mutex profiling and the amount of
> work getting done is pretty high -- we should be able to reap a lot of
> benefit by doing even a little less work there.

Like I said, setting up a VM mapping is very inefficient in FreeBSD.
This, and the fd allocation issue which I fixed earlier this year,
were the two areas where fefe's scalability benchmark really trounced
us last October.

DES
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Dag-Erling Sm=F8rgrav - des@des.no