Re: Absolutely horrid IDE performance...

Gerard Roudier (
Sat, 5 Dec 1998 01:13:57 +0100 (MET)

On Wed, 2 Dec 1998, Mark Lord wrote:

> > -------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
> > 256 17374 95.5 32681 33.2 10706 24.3 15683 68.4 23710 24.3 214.6 1.8

Just my comments on this benchmark results:

1) Block write = 32681 KB/second
Comment: Not relevant, if as I guess the machine has probably 128 MB

2) Block read 23710 KB/second against Character Read 15683 KB/s
and only 68.4 % CPU.
Comment: You should get at least 90 %. Something is behaving not well

For your information, here is a benchmark result with Linux 2.1.30 and the
stock driver I got a couple of days ago using a single Cheatah2.
(PII 233 / 66MHz SDRAM + 64MB + SYM53C895)

-------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
4K ext2 300 10656 97.7 19235 23.7 8346 26.5 13097 91.8 18602 21.0 229.2 4.7

Even if the number are lower, I bet you that a single Cheatah2 is
significantly faster for RL than you pair of IDE things. Just looking at
the results shows that the Cheatah2 is working in optimal conditions. On
the other hand the IDE things seem to perform chaotically due to the
poorness of the IDE interface and protocol.

(BTW, results seem slightly better using the 896 board I have received
yesterday using the new 896 driver (less CPU load and a bit faster).


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