lkml.org 
[lkml]   [2003]   [Apr]   [16]   [last100]   RSS Feed
Views: [more markup]  [less markup]  [headers]  [forward] 
 
Messages in this thread
/
DateWed, 16 Apr 2003 12:36:54 +0400
FromIvan Kokshaysky <>
SubjectRe: DMA transfers in 2.5.67
On Wed, Apr 16, 2003 at 12:09:00AM +0200, MЕns RullgЕrd wrote:
> Btw, I just noticed that hard disk throughput is much lower with 2.5
> than 2.4.  With 2.4.21-pre5 I get ~40 MB/s, but with 2.5.67 the speed
> drops to 25-30 MB/s.  Everything according to hdparm.  Is it possible
> that DMA is generally slow for some reason?

Possible reason is that in 2.4 we've forced reasonable latency timer
value for all PCI devices, while in 2.5 we haven't as yet.

Ivan.
-
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 12:34    [from the cache]
©2003-2008