Jens Axboe wrote:
> On Tue, 2005-07-05 at 15:02 +0200, Ondrej Zary wrote:
> 
>>>Ok, looks alright for both. Your machine is quite slow, perhaps that is
>>>showing the slower performance. Can you try and make HZ 100 in 2.6 and
>>>test again? 2.6.13-recent has it as a config option, otherwise edit
>>>include/asm/param.h appropriately.
>>>
>>
>>I forgot to write that my 2.6.12 kernel is already compiled with HZ 100 
>>(it makes the system more responsive).
>>I've just tried 2.6.8.1 with HZ 1000 and there is no difference in HDD 
>>performance comparing to 2.6.12.
> 
> 
> OK, interesting. You could try and boot with profile=2 and do
> 
> # readprofile -r
> # dd if=/dev/hda of=/dev/null bs=128k 
> # readprofile > prof_output
> 
> for each kernel and post it here, so we can see if anything sticks out.
> 
Here are the profiles (used dd with count=4096) from 2.4.26 and 2.6.12 
(nothing from 2.6.8.1 because I don't have the .map file anymore).

-- 
Ondrej Zary