On Tue, 9 Apr 1996 17:51:34 -0700 (PDT)  Curt Sampson wrote:

> This is just a thought, but has there been any attempt to analyse
> the CPU usage of filesystem operations and perhaps optimise them?
> I've got a 486/100 with an NCR controller and a P90 with a Buslogic
> controller, both with an HP Surestore 5400 RPM disk drive (among
> others). Using iozone, the P90 gets about 4MB/sec on the HP drive,
> the 486/100 gets about 1.5 MB/sec. The results on the 486/100 vary
> depending on whether the filesystem is small or large, and how full
> it is. The P90 doesn't. This leads me to suspect that something in
> the CPU may be a limiting factor here.
> 
> Then again, perhaps I'm completely off base.

If you're interested in looking at CPU utilitisation, there's a program
called 'bonnie' that I've always found to be a bit more useful than
IOZONE.  It's public domain; I can send anyone a copy if they want
it.

A sample output is included below:

	      -------Sequential Output-------- ---Sequential Input-- --Random--
	      -Per Char- --Block--- -Rewrite-- -Per Char- --Block--- --Seeks---
Machine    MB K/sec %CPU K/sec %CPU K/sec %CPU K/sec %CPU K/sec %CPU  /sec %CPU
sun.2.9G 2000  2287 95.9  2304 35.0   607 15.4  1994 99.0  4440 55.8  63.8 13.6

Simon.
--
Simon Burge						simonb@telstra.com.au
UNIX Support, CPR Project, Telstra.			+61 3 9634 3974
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Sometimes it only goes half-way around, and then does a lap of honor - Jimeoin.