multi-processor multi-tasking

I have a need to utilize the additional processors that are now coming in windows boxes. I had assumed that adding threads would automatically utilize these extra processes and I was surprised to learn I was wrong. I have the 'affinity' for SF.EXE set to both CPU1 and CPU0 in the windows task manager and when I run the following from the command line I use 50% of the CPU on the performance graph. In fact, sometimes one or the other processor is more heavily used during this operation.

The code snip-it included below is the heart of a monte-carlo simulation program. The actual calculations in CHAIN are rather extensive and take many seconds for the full set of experiments to complete. When I tried running the experiments in 2 tasks Q1 and Q1 the CPU usage dropped to only 35-40% and the time to finish extended accordingly. I then added QQ1 AND QQ2 to increase the priority of the threads. I now can get back to the 50% CPU utilization I had with a single task, but the other CPU is still not being utilized.

Does anyone have information on how to gain full attention of both CPU's?

Thanks, Ken B

<snip-it>

1000 to #gates
100 to #exp

: EXPERIMENT
    /GATES
    GATE RATES /. TO MicroS/Fs
    0 0 ET 2!
    0 \ INITIAL TIME
    #GATES 0 DO
        GATES{{ @ I [ |GATES| 1 - ] LITERAL AND |EPSILON| * + ^GATE !
        GATE NEGATE +
        BEGIN
            DUP 0<
        WHILE
            MicroS/Fs TIME
            DUP ET 2@ ROT M+ ET 2!
            +
            CHAIN
        REPEAT
        GATE>FEYNMAN
    LOOP
    NEGATE ET 2@ ROT M+ ET 2!
    ;

: EXPERIMENTS ( SUMS INTO PREVIOUS TALLEYS )
    /GATES
    #EXP |EXP| MIN 0 DO PAUSE
        EXPERIMENT
    LOOP
    ;

8192 TASK TASK1
8192 TASK TASK2

: Q1 TASK1 ACTIVATE EXPERIMENTS GATES{{ @ FREE TO malloc-fail? TERMINATE ;
: Q2 TASK2 ACTIVATE EXPERIMENTS GATES{{ @ FREE TO malloc-fail? TERMINATE ;

Function: SetThreadPriority ( a b -- x )
: qq1 q1 task1 taskhandle THREAD_PRIORITY_HIGHEST SetThreadPriority . ;
: qq2 q2 task1 taskhandle THREAD_PRIORITY_HIGHEST SetThreadPriority . ;

Dr. Kenneth B Butterfield

phone: 505 667 8944

PO Box 1663
ms J562
Los Alamos National Laboratory
Los Alamos New Mexico 87545

"I do not trust a computer that I am not carrying!"

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Received on Wed May 09 2007 - 11:51:05 PDT