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Old 2011-01-02, 16:01   #7
Mr. P-1
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Jun 2003

7×167 Posts

Originally Posted by Neo View Post
Well, I think I am coming to the conclusion that dedicating an entire system to this 100MD LL assignment for at least year would not be a good use of CPU cycles. I am going to finish p-1 factoring (completing 1.5% a day with only 1 core - going to bump that up to two cores today) and then I will unassign the LL test.
If your goal is to make best use of CPU cycles, then I suggest you consider leaving the P-1 to just one core. The conventional wisdom, which I've no doubt is correct, is that giving your cores independent assignments is more efficient overall. Sure, you won't be done with this assignment for a longer time, but it's not like there is anyone waiting for it.

Also, if your goal is to make the biggest contribution you can to GIMPS progress with your available hardware, then consider devoting at least one core to P-1 on each machine that you can grant enough memory to do a good stage 2. (about 500MB). With all worktypes, if you don't do it, someone else will. But with P-1 the likelihood is that the someone else won't do it nearly as well as you. Roughly half of all exponents never get a P-1 stage 2, and many that do, do so on machines that can devote relatively little memory to the task.

I have other suggestions, but I won't bombard you with them, especially as I don't know whether this kind of optimisation interests you.

Last fiddled with by Mr. P-1 on 2011-01-02 at 16:06
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