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Old 2009-09-14, 00:13   #1
TomYosho
 

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Default Quad Core Questions...

I'm not sure if I'm posting this in the right section... but a moderator could just move it to the appropriate section if it's not. I have an Intel Q9550 at stock frequency (2.83ghz) with 4 gigs of pc2-6400 ram at 5-4-4-12. I have the program assign what ever work makes the most sense. (LL testing right now.) Here are the few questions I have... - If I run 4 worker threads would that saturate my memory bandwidth? - Would it be more efficient (quicker) to run 2, 3, or 4 worker treads? - How much ram should I allocate to prime95?
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Old 2009-09-14, 06:33   #2
joblack
 
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Quote:
Originally Posted by TomYosho View Post
I'm not sure if I'm posting this in the right section... but a moderator could just move it to the appropriate section if it's not. I have an Intel Q9550 at stock frequency (2.83ghz) with 4 gigs of pc2-6400 ram at 5-4-4-12. I have the program assign what ever work makes the most sense. (LL testing right now.) Here are the few questions I have... - If I run 4 worker threads would that saturate my memory bandwidth? - Would it be more efficient (quicker) to run 2, 3, or 4 worker treads? - How much ram should I allocate to prime95?
The fastest solution is 2 worker threads with two helper threads. RAM resources depends on the number you calculate ... you can give every thread around 600 MB that's more than enough.
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Old 2009-09-14, 13:01   #3
lycorn
 
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If you stick to 1st time LL testing (which, per the current server defaults, is the most appropriate for your hardware), you donĀ“t have to worry about memory allocation, for that type of work uses very little memory (a few tens of MB per worker window).
The setup proposed by joblack (2 workers, 2 threads each) appears to be the best in terms of overall throughput.

Last fiddled with by lycorn on 2009-09-14 at 13:03
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