lkml.org 
[lkml]   [2000]   [Oct]   [11]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
Subject36 bit MTRRs, Re: test10-pre1 problems on 4-way SuperServer8050
On Wed, 11 Oct 2000, Tigran Aivazian wrote:
> I will continue to narrow down by removing some things (like mtrr) from
> the equation. Rik, the problem is that when one enables PAE (or just
> highmem-4G) support on a 4-way 6G RAM machine becomes 38-40 times slower.

Will you please try this patch? This is almost the same as I
sent to you before, it is just against 2.4.0-test10-pre1 and
it lacks the corrections to e.g. the frame buffer drivers.

I am now running test10-pre1 with this patch and:

---------------------------------------------------------
[root@localhost /root]# cd /proc
[root@localhost /proc]# cat mtrr
reg00: base=0x00000000 ( 0MB), size= 128MB: write-back, count=1
reg05: base=0xe2000000 (3616MB), size= 32MB: write-combining, count=1
[root@localhost /proc]# echo "base=0x200000000 size=0x100000000 type=write-combining" >mtrr
[root@localhost /proc]# cat mtrr
reg00: base=0x00000000 ( 0MB), size= 128MB: write-back, count=1
reg01: base=0x00200000000 ( 8192MB), size= 4096MB: write-combining, count=1
reg05: base=0xe2000000 (3616MB), size= 32MB: write-combining, count=1
----------------------------------------------------------

This is on a dual P-III machine with 128 MB memory.
If it causes problems on Athlons then change the line

#define AMD_OR_MASK (0xfffff000UL)

to

#define AMD_OR_MASK (INTEL_OR_MASK)

and recompile and tell me what happens. Also, I would like to hear
reports from non-Intel (Cyrix, etc.) and older AMD machines.
I do not have my Cyrix 6x86MX anymore but this scheme worked on that.

Regards,
Zoltan Boszormenyi
[unhandled content-type:application/octet-stream]
\
 
 \ /
  Last update: 2005-03-22 12:39    [W:0.079 / U:4.152 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site