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Subject: Re: Was waiting for an answer from Hyatt but...

Author: Robert Hyatt

Date: 19:44:27 10/21/05

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On October 21, 2005 at 18:29:59, joseph soney wrote:

>He seems to never be on anymore. Can anyone one out there help!?
>
>Dr. Hyatt,
>My bussiness currently has the same system you used for the WCCC05. I benched
>crafty with 8cpus enabled and to my suprise it only benched at 4.4mil nodes per
>second. I am uses a 64 bit crafty 20.1 and windows server 2003 x64. What could
>the problem be? At start up it says numa set to 4 nodes with the nodes
>containing 0-7 cpus is this right? Please help. Interesting enough I set cpu to
>use 4cpu and got a bench of 5.9mil??? Please help!
>
>
>Thanks so much
>Joe


I am not sure what is happening.  First test is to open a command prompt window,
crank up crafty, and run bench with 1 cpu.  Note the NPS.  Repeat for 2. If NPS
is not near 2.0x (at least 1.9X) the 1 cpu NPS, something is wrong.  Continue to
add a processor (mt=0, mt=2, mt=3, mt=4, ..., mt=8) and each time the NPS should
go up proportionally, with 8 cpus, if the NPS is not 7.5X the 1 cpu NPS, or
better, then something is definitely up...

Next test.  Open 8 command prompt windows, and start a 1-cpu crafty in each, and
run bench.  See if all 8 now run at nearly exactly the same speed as just one
runs.  If not, make _sure_ windows is seeing 8 cpus, and that you are not
running anything else on the machine.  Also watch to make sure the hash table is
not too large for your available memory...

The WCCC05 log files have been on my ftp machine for quite a while.  You can
download one and look at the NPS the log shows for the 4 x 875 box, and compare
that to yours, noticing that I was running Suse 9.3 linux and gcc, where you are
running windows and MSVC which should be faster due to the better compiler...

make sure you have the optimizations set right of course...

make sure the system BIOS is set to NUMA, not "interleaved memory"...




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