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Message boards :
Number crunching :
Are Work Units Run on Cores or Threads
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Hi everyone hope everyone is keeping well
I have a question are the work units run on cores or threads CPU? I would ideally would like to run on threads if it is at all possible. or is that not possible?
Thank you.
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 Vato Volunteer tester
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Assuming I understand your question...
LLR subprojects need cores for certain - HT threads don't have access to enough floating point units to make any sense - and most of the LLR tasks need lots of L3 cache anyway. LLR does multithread with good effect, but each thread needs to utilise an entire core.
CPU sieve e.g. 321 Sieve, can run well with HT threads though.
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Thank you Vato,
you got what I was saying so each work unit needs a Core to run, so 321 sieve also need a core a work unit as well? :-)
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VatoVolunteer tester
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321 Sieve will run single-threaded, but multiple tasks.
e.g. if you have a 4 core machine, you can run 4 tasks concurrently, or if you have HT enabled and "use at most 100% of the CPUs" set, you can run 8 tasks concurrently.
With LLR tasks, and HT enabled, you would want "uset at most 50% of the CPUs".
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Michael GoetzVolunteer moderator
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I can make this one simple...
LLR: cores
Sieves: threads
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My lucky number is 75898524288+1 | |
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To get the most out of one machine with 4 cores, 8 threads and 1 video card what would be the best setup. I have set video card to sieve which I believe needs 1 part of a core to feed it, how should I set my cores and thread to work for LLR work?
I have Xeon E3-1240 v3 4C/8T with Quadro K600 card
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I can make this one simple...
LLR: cores
Sieves: threads
This means that for LLR projects, you have to make sure your system does not decide to run on [all] threads, because if it does, that is inefficient.
So Vato's posts tell how to do that. Either turn off hyper-threading in the BIOS. Or else set "use at most 50% of the CPUs" in your account at www.primegrid.com.
So your question "possible or not possible" is to be understood like this.
/JeppeSN | |
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RafaelVolunteer tester
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To get the most out of one machine with 4 cores, 8 threads and 1 video card what would be the best setup. I have set video card to sieve which I believe needs 1 part of a core to feed it, how should I set my cores and thread to work for LLR work?
I have Xeon E3-1240 v3 4C/8T with Quadro K600 card
PPS Sieve uses very little CPU time, so you can ignore that. Higher n GFN also fillow this pattern, if you want to try to hunt for primes instead.
For the rest, it depends on what you want to do. You can hunt small primes, big primes or work on sieving, and they all have different ways to optimize your machine. | |
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Message boards :
Number crunching :
Are Work Units Run on Cores or Threads |
