lkml.org 
[lkml]   [2004]   [Jan]   [7]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
SubjectRe: Strange IDE performance change in 2.6.1-rc1 (again)
Date
On Wednesday 07 January 2004 20:23, Ram Pai wrote:
>
> I tried on my lab machine with scsi disks. (I dont have access currently
> to a spare machine with ide disks.)
>
> I find that reverting the changes in mm/filemap.c and then reverting the
> lazy-read optimization gives much better sequential read performance on
> blockdevices. Is this your observation on IDE disks too?

Yes and No.
I have only tried to revert lazy-read optimization (without any visible
change) so I have reapplied it AND THAN I have reverted changes in
mm/filemap.c... and performance has gone back.

>
> > I don't know why... but it does.
>
> Lets see. I think my theory is partly the reason. But the changes in
> filemap.c seems to be influencing more.

YES, I agree.
I haven't done a lot of tests but it seems to me that the changes in
mm/filemap.c are the only things that influence the sequential read
performance on my disk.

--
Paolo Ornati
Linux v2.4.23

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2005-03-22 13:59    [W:0.107 / U:1.372 seconds]
©2003-2014 Jasper Spaans. Advertise on this site