Skip site navigation (1)Skip section navigation (2)
Date:      Sun, 21 Mar 2010 17:30:52 +0100
From:      Ulrich =?utf-8?B?U3DDtnJsZWlu?= <uqs@spoerlein.net>
To:        Scott Long <scottl@samsco.org>
Cc:        freebsd-current@freebsd.org, Alexander Motin <mav@freebsd.org>, freebsd-arch@freebsd.org
Subject:   Re: Increasing MAXPHYS
Message-ID:  <20100321163051.GT99813@acme.spoerlein.net>
In-Reply-To: <891E2580-8DE3-4B82-81C4-F2C07735A854@samsco.org>
References:  <4BA4E7A9.3070502@FreeBSD.org> <201003201753.o2KHrH5x003946@apollo.backplane.com> <891E2580-8DE3-4B82-81C4-F2C07735A854@samsco.org>

next in thread | previous in thread | raw e-mail | index | archive | help
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



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20100321163051.GT99813>