Subject: general striping parameters for FFS on CCD or RAIDframe
To: None <tech-kern@netbsd.org>
From: Erik E. Fair <fair@netbsd.org>
List: tech-kern
Date: 06/25/2003 02:59:16
Has anyone looked into CCD or RAIDframe performance enough to be
able to suggest general rules for setting the stripe size for best
performance with FFS, as some function of, say,

	1. disk cache size (the on-HDA cache, that is)

	2. FFS block/frag size to be used
		(i.e. typical I/O transaction size)

	3. number of disks

	4. SCSI versus IDE/ATAPI (versus USB or FireWire)

	5. [...] 

What I'm hoping for is some rules that will give, say, 90% of what
perfect tuning might deliver, without getting too specific with
particular configurations (e.g. "for Seagate on IDE, do this; for
IBM on IDE, do this...").

	Erik <fair@netbsd.org>