Re: Interesting disk throughput performance problem

From: Jimmie Mayfield (
Date: Tue Jul 24 2001 - 10:06:35 EST

On Sun, Jul 22, 2001 at 06:44:38AM -0400, Mike Black wrote:
> Not enough info (plenty for guessing though :-)
> First off show "hdparm -i /dev/hd_" and "hdparm /dev/hd_" -- this will
> ensure both drives have things like DMA, etc.
> Next -- you didn't say what benchmarks you're using locally.
> And as the previous poster said provide "cat /proc/interrupts".

/proc/interrupts looks like this:
  0: 17319250 XT-PIC timer
  1: 85980 XT-PIC keyboard
  2: 0 XT-PIC cascade
  5: 1084144 XT-PIC ide3, usb-uhci, usb-uhci
  6: 811 XT-PIC floppy
  9: 1284463 XT-PIC mga@PCI:1:0:0
 10: 142416 XT-PIC eth0
 11: 8296678 XT-PIC eth1, C-Media PCI CM8738
 12: 385915 XT-PIC PS/2 Mouse
 15: 7 XT-PIC ide1
NMI: 0
LOC: 17319087
ERR: 3022
MIS: 0

I would like to make a correction to my original post. In that post I said
that the drives are "masters" on their own controller. This was false.
They share a controller (CMD 649) with the Maxtor drive being "master" and
the IBM drive being "slave". To test if this was the problem, I reran the
tests (see URL below) with the IBM drive completely disconnected. I didn't
notice any difference.

I collected my benchmarks and tests into a simple webpage to avoid cluttering
this list. Hopefully someone will see something obvious that I've


Jimmie Mayfield       email:
My mail provider does not welcome UCE --

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This archive was generated by hypermail 2b29 : Tue Jul 31 2001 - 21:00:16 EST