Memory Settings

Fred · 2016-02-05, 14:36

My understand is that Prime95 doesn't require a lot of memory, but when setting up Prime95 you get a warning if you stick with the default 8mb Day / 8mb night. So, clearly a higher value is optimal, but how much is "ideal" and how much is just overkill (assuming LL tests)?

For example, I currently have the following:

Computer Memory 16334 MB configured usage 3500 MB day / 3500 MB night

As it's crunching away on a FT LL, it looks like it's actively using 75mb. However I believe I read somewhere it may use more toward the start or end of an LL test when it's doing some other work? So with my current settings it could use up to 3500mb as needed during those parts of the testing?

chalsall · 2016-02-05, 14:44

Quote:

Originally Posted by Fred

As it's crunching away on a FT LL, it looks like it's actively using 75mb. However I believe I read somewhere it may use more toward the start or end of an LL test when it's doing some other work? So with my current settings it could use up to 3500mb as needed during those parts of the testing?

The larger memory demand is only if a machine is doing P-1'ing before starting the LL'ing.

However, lately almost no candidates are ever assigned for LL'ing or DC'ing without P-1 already having been done. There are "specialists" who focus on doing the P-1'ing for others to then do the LL'ing, much like there are "specials" who first do the TF'ing for the P-1'ers.

But if you leave your settings as they are, you'll be fine; the allowed memory will simply never be used.

LaurV · 2016-02-05, 15:20

Stage 2 of P-1 and Stage 2 of ECM benefit from a lot of RAM. Having a lot of memory during those types of work increase your chance of finding a factor. But it is not necessary, and if you only do LL, you are good with the default settings. Your settings (3.5G) are ok, P95 will only use a little of it, the functionality is not affected.

kladner · 2016-05-02, 23:26

This seems a good place to ask, "When I have 28600 MB available, why does Stage 2 only use 17599 MB, with 480 Relative Primes?"

Prime95 · 2016-05-03, 00:37

Quote:

Originally Posted by kladner

This seems a good place to ask, "When I have 28600 MB available, why does Stage 2 only use 17599 MB, with 480 Relative Primes?"

The next "step" is 960 relative primes.

kladner · 2016-05-03, 00:51

Quote:

Originally Posted by Prime95

The next "step" is 960 relative primes.

Ah! OK. Presumably requiring 35198 MB of RAM.

2016-02-05, 14:36	#1
Fred "Ron" Jan 2016 Fitchburg, MA 61₁₆ Posts	Memory Settings My understand is that Prime95 doesn't require a lot of memory, but when setting up Prime95 you get a warning if you stick with the default 8mb Day / 8mb night. So, clearly a higher value is optimal, but how much is "ideal" and how much is just overkill (assuming LL tests)? For example, I currently have the following: Computer Memory 16334 MB configured usage 3500 MB day / 3500 MB night As it's crunching away on a FT LL, it looks like it's actively using 75mb. However I believe I read somewhere it may use more toward the start or end of an LL test when it's doing some other work? So with my current settings it could use up to 3500mb as needed during those parts of the testing? Last fiddled with by Fred on 2016-02-05 at 14:36

2016-05-02, 23:26	#4
kladner "Kieren" Jul 2011 In My Own Galaxy! 23656₈ Posts	This seems a good place to ask, "When I have 28600 MB available, why does Stage 2 only use 17599 MB, with 480 Relative Primes?" Attached Thumbnails

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2016-02-05, 15:20	#3
LaurV Romulan Interpreter "name field" Jun 2011 Thailand 10276₁₀ Posts	Stage 2 of P-1 and Stage 2 of ECM benefit from a lot of RAM. Having a lot of memory during those types of work increase your chance of finding a factor. But it is not necessary, and if you only do LL, you are good with the default settings. Your settings (3.5G) are ok, P95 will only use a little of it, the functionality is not affected.