lkml.org 
[lkml]   [2003]   [Jul]   [30]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [RFC] block layer support for DMA IOMMU bypass mode II
From
Date
On Tue, 2003-07-29 at 23:42, Grant Grundler wrote:
> On Mon, Jul 28, 2003 at 01:15:13PM +0200, Andi Kleen wrote:
> > Run it with 100-500 users (reaim -f workfile... -s 100 -e 500 -i 100)
>
> jejb was wondering if 4k pages would cause different behaviors becuase
> of file system vs page size (4k vs 16k). ia64 uses 16k by default.
> I've rebuilt the kernel with 4k page size and VMERGE != 0.
> The substantially worse performance feels like a rat hole because
> of 4x pressure on CPU TLB.

OK, I admit it, it was a rat hole. Provided reaim uses large files, we
should only get block<->page fragmentation at the edges, and obviously,
reaim has to use large files otherwise it's not testing the virtual
merging properly...

James


-
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 13:47    [W:0.126 / U:33.152 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site