Re: Problem with Asus P4C800-DX and P4 -Northwood-

From: Paulo Marques
Date: Mon Jul 25 2005 - 09:01:54 EST


Andreas Baer wrote:
[...]
Vmstat for Notebook P4 3.0 GHz 512 MB RAM:

procs -----------memory---------- ---swap-- -----io---- --system-- ----cpu----
r b swpd free buff cache si so bi bo in cs us sy id wa
1 0 0 179620 14812 228832 0 0 33 21 557 184 3 1 95 1
2 0 0 178828 14812 228832 0 0 0 0 1295 819 6 2 92 0
1 0 0 175948 14812 228832 0 0 0 0 1090 111 37 17

This vmstat output doesn't show any input / output happening. Are you sure this was taken *while* your test is running? If it is, then all files are already in pagecache. The fact that you have free memory at all times, and that the run on the notebook takes less than 20 seconds confirms this.

The second takes a lot more time to execute. The 1Gb memory does make me suspicious, though.

There is a known problem with BIOS that don't set up the mtrr's correctly for the whole memory and leave a small amount of memory on the top with the wrong settings. Accessing this memory becomes painfully slow.

Can you send the output of /proc/mtrr and try to boot with something like "mem=768M" to see if that improves performance on the Desktop P4?

--
Paulo Marques - www.grupopie.com

It is a mistake to think you can solve any major problems
just with potatoes.
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