On Thu, Oct 05, 2000 at 08:55:43PM -0600, Greg Oster wrote:
> 
> You're running into a couple of things here:
>  1) with 3 disks for data (and one for parity) for each stripe, it's 
> impossible to pick an even "chunk" size such that you arn't always doing
> at least one "small write" (i.e. read old data, read old parity, write new 
> data, write new parity) per IO.  Using 3 drives or 5 drives allows things to 
> be split up more evenly, and should yield better performance (at least for 
> writes).

This isn't necessarily as bad as it seems.  You can manipulate the
filesystem's "maxcontig" value to get 48K instead of 64K clustered
reads/writes, and so forth.

-- 
Thor Lancelot Simon	                                      tls@rek.tjls.com
	the effort to perceive simply the cruel radiance of what is