Re: Absolutely horrid IDE performance...
Mark Lord (mlord@pobox.com)
Wed, 25 Nov 1998 14:57:14 +0000
Brian Macy wrote:
..
> On /dev/hda:
> hdparm gives 6.68meg/sec
..
> On /dev/sda (a junker Seagate WSCSI on the Mylex controller:
> hdparm varies greatly between 2.5meg/sec and 4.5meg/sec
> time dd... gives 4.6meg/sec
>
> Can anyone explain the discrepancy? I can't see why there would be such a
> huge difference. From what I've experienced with 95/NT machines, the IBM
> UDMA drives are very fast. Linux even shows the system time required to be
> reasonable between SCSI/IDE... it just seems like the drive is just running
> slow (I thought it might be CPU overhead).
Nope. CPU overhead is less for IDE than for SCSI.
Upgrade to hdparm-3.5 so that you can display the
drive's current UDMA mode. The BIOS may have selected mode0
instead of the faster mode2.
Ooops.. wait a minute.. you said:
>ide: i82371 PIIX (Triton) on PCI bus 0 function 57
The Intel PIIX chip does not support UDMA.
Are you not running a 2.1.xxx kernel??? You should be!
--
mlord@pobox.com
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