Jens Axboe <axboe@suse.de> writes:

> hpt366 has no special work arounds or stuff it disables, it can't be
> anything like that.
> 

Followup on the problem. Yesterday I was upgrading my Debian Linux. To
do that I have to remount /usr read-write. After the update finished,
I tested once again disk writing speed. And there it was, full
22MB/sec (on the same partition). And once I get to that point, disk
will remain performant. Then I thought (poor man's logic) that poor
performance might have something to do with my /usr mounted read-only
(BTW, it's on the same disk I'm having problems with).

Quick test: reboot (/usr is ro), check speed -> only 8MB/sec, remount
/usr rw, but unfortunately didn't help, writing speed remains low.

So it was just an idea. I still don't know what can be done to return
speed to normal. I don't know if I have mentioned, but reading from
the same disk is always going at the full speed.

Also, I'm pretty sure that I have the same problem on the completely
another machine (at the work) which doesn't use HPT366, but standard
controller (BX chipset).

So, something might be wrong with my setup, but I'm still unable to
find what.

I'm compiling with 2.95.4 20011006 (Debian prerelease) from the Debian
unstable distribution. Kernel is completely monolithic (no modules).

Attached is the _relevant_ part of IDE configuration.