Re: Slow Disk I/O with QPS M3 80GB HD

[H . J . Lu]

On Mon, Dec 10, 2001 at 08:34:52PM -0800, H . J . Lu wrote:
> I have a very strange problem. The disk I/O of my QPS M3 80GB HD is
> very slow under 2.4.10 and above. I got like 1.77 MB/s from hdparm.
> But under 2.4.9, I got 14 MB/s on the same hardware. A 30GB HD has
> consistent I/O performance under 2.4.9 and above on the same bus. Has
> anyone else seen this? Does anyone have a large (>= 80GB) 1394 HD?
> 

I did a binary search. 2.4.10-pre10 is the last good kernel. I got

# hdparm -t /dev/sda

/dev/sda:
 Timing buffered disk reads:  64 MB in  4.40 seconds = 14.55 MB/sec

Even since 2.4.10-pre11 up to 2.4.16, I got about 1.77 MB/sec on the
same hardware. However, I don't have problems with 80GB IDE HD. Has
anyone seen I/O problems on large (>= 80GB) SCSI HD or HD with SCSI
emulation?

H.J.