This is probably answered elsewhere, but I can't find it. If you see it, please point me to the post.
I have a CPU with 18 threads free. Which of the following configurations would be best for PPD (and explain your logic of your answer).
18 threads, 1 process
9 threads, 2 process
6 threads, 3 process
3 threads, 6 process
2 threads, 9 process
1 thread, 18 process
I don't think I can do fractional threads
Any thoughts?
(I would think that 18 threads, 1 process would crunch information the fastest and give the most PPD, but that is only a guess on my part)
Do you want to partition threads on a CPU?
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Re: Do you want to partition threads on a CPU?
One process of 18 threads (F@H calls them CPUs) should yield the most Points per Day.
The Quick Return Bonus is nonlinear so two processes may do the same science, yet yield less PPD.
The Quick Return Bonus is nonlinear so two processes may do the same science, yet yield less PPD.
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I tried to remain childlike, all I achieved was childish.
A friend to those who want no friends
Re: Do you want to partition threads on a CPU?
I' going to assume to get 18 CPUs, you've taken into account the other threads in a logical manner.
What you cannot predict is whether there will always be a supply of WUs that use all 18 threads/(cpus). With that assumption, yes, 18 is good.
Every project has a range of thread counts that it is allowed to run on. Suppose the only WUs that are available run on CPUs<=16 (or some other number. You'll get that assignment and two threads will be idle for the duration of the processing of that assignment. You might do better with a 9+9 configuration for some percentage of the time. There's no rational way to predict what projects will be available and for what percentage of the time.
What you cannot predict is whether there will always be a supply of WUs that use all 18 threads/(cpus). With that assumption, yes, 18 is good.
Every project has a range of thread counts that it is allowed to run on. Suppose the only WUs that are available run on CPUs<=16 (or some other number. You'll get that assignment and two threads will be idle for the duration of the processing of that assignment. You might do better with a 9+9 configuration for some percentage of the time. There's no rational way to predict what projects will be available and for what percentage of the time.
Posting FAH's log:
How to provide enough info to get helpful support.
How to provide enough info to get helpful support.