FreeBSD 5.3b7and poor ata performance

[Kevin Oberman]

> Date: Fri, 15 Oct 2004 20:06:12 +0200
> From: fandino <fandino at ng.fadesa.es>
> Sender: owner-freebsd-current at freebsd.org
> 
> Hello,
> 
>   This is an interesting issue. While I was installing  FreeBSD 5.3b7
> I wonder about the performance that the new branch will bring to my
> computer, and it was a deception how bad FreeBSD performs compared
> with Linux on the same hardware (even I repeat the test on different PC
> with identical results).
> 
> Tests were done win bonnie++ 1.93c and the results were Linux two
> times faster than FreeBSD using the same hardware.
> 
> GNU/Linux 2.4.18 with ext2:               56848 K/sec
> FreeBSD 5.3b7 with default fs:            26347 K/sec
> FreeBSD 5.3b7 ata raid0* (two disks):     26131 K/sec
> FreeBSD 5.3b7 geom stripe* (two disks):   30063 K/sec

Are you comparing apples with apples? I believe that Linux mounts file
systems as async by default. To compare with FreeBSD, you should use "-o
async" when you mount. Of course, this is less reliable.

Also, make sure that disk write-cache is enabled on both or disabled on
both. 
-- 
R. Kevin Oberman, Network Engineer
Energy Sciences Network (ESnet)
Ernest O. Lawrence Berkeley National Laboratory (Berkeley Lab)
E-mail: oberman at es.net			Phone: +1 510 486-8634