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Old 2016-02-05, 14:36   #1
Fred
 
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"Ron"
Jan 2016
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Default 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
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Old 2016-02-05, 14:44   #2
chalsall
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Quote:
Originally Posted by Fred View Post
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.
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Old 2016-02-05, 15:20   #3
LaurV
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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.
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Old 2016-05-02, 23:26   #4
kladner
 
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"Kieren"
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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?"
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Old 2016-05-03, 00:37   #5
Prime95
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Quote:
Originally Posted by kladner View Post
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.
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Old 2016-05-03, 00:51   #6
kladner
 
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Quote:
Originally Posted by Prime95 View Post
The next "step" is 960 relative primes.
Ah! OK. Presumably requiring 35198 MB of RAM.
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