Abysmal mly Extreme RAID performance in 5.0-p7?

[Chris Dillon]

On Wed, 21 May 2003, Jaye Mathisen wrote:

> 206438400 bytes transferred in 27.405360 secs (7532775 bytes/sec)

What were the exact dd options you used for this?  If you didn't
specify a block size, the default block size of 512 bytes is used, and
you will get dismal performance figures no matter what kind of
hardware you have.  Increase the block size to at _least_ 64KB.  I
believe 128KB is the maximum block size FreeBSD will use, so testing
with block sizes above that won't matter much.

-- 
 Chris Dillon - cdillon(at)wolves.k12.mo.us
 FreeBSD: The fastest and most stable server OS on the planet
 - Available for IA32 (Intel x86) and Alpha architectures
 - IA64, PowerPC, UltraSPARC, ARM, and S/390 under development
 - http://www.freebsd.org

No trees were harmed in the composition of this message, although some
electrons were mildly inconvenienced.