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Date: Sun, 21 Mar 2010 17:30:52 +0100
From: Ulrich =?utf-8?B?U3DDtnJsZWlu?= <uqs@spoerlein.net>
To: Scott Long <scottl@samsco.org>
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Cc: freebsd-current@freebsd.org, Alexander Motin <mav@freebsd.org>,
	freebsd-arch@freebsd.org
Subject: Re: Increasing MAXPHYS
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On Sat, 20.03.2010 at 12:17:33 -0600, Scott Long wrote:
> Windows has a MAXPHYS equivalent of 1M.  Linux has an equivalent of an
> odd number less than 512k.  For the purpose of benchmarking against these
> OS's, having comparable capabilities is essential; Linux easily beats FreeBSD
> in the silly-i/o-test because of the MAXPHYS difference (though FreeBSD typically
> stomps linux in real I/O because of vastly better latency and caching algorithms).
> I'm fine with raising MAXPHYS in production once the problems are addressed.

Hi Scott,

while I'm sure that most of the FreeBSD admins are aware of "silly"
benchmarks where Linux I/O seems to dwarf FreeBSD, do you have some
pointers regarding your statement that FreeBSD triumphs for real-world
I/O loads? Can this be simulated using iozone, bonnie, etc? More
importantly, is there a way to do this file system independently?

Regards,
Uli