help!

2012-02-11, 07:10

Can I get the prime95 to test 1 number with all cores at the same time? if so, how?

LaurV · 2012-02-11, 11:46

You can, but it does not make too much sense. For a 4-cores or a 6-cores intel, adding more then 3 cores to the same exponent, generally does not improve the timing, as exchanging data become costly, if you fragment the task too much you spend time putting it together again.

To see the results for your computer, use Options/Benchmark from p95's menu and think about the best combination for your computer. Then play with the number of cores and multitrthreading on Test/Workers menu.

bcp19 · 2012-02-11, 16:25

To use multiple cores on a single exponent, click Test, then select Worker Windows. On the scrteen that pops up, set number of Worker Windows to run to 1 and then set CPUs to use to however many cores you have.

Christenson · 2012-02-12, 03:43

Quote:

Originally Posted by LaurV

You can, but it does not make too much sense. For a 4-cores or a 6-cores intel, adding more then 3 cores to the same exponent, generally does not improve the timing, as exchanging data become costly, if you fragment the task too much you spend time putting it together again.

To see the results for your computer, use Options/Benchmark from p95's menu and think about the best combination for your computer. Then play with the number of cores and multitrthreading on Test/Workers menu.

LaurV, it doesn't make sense in terms of directly advancing the GIMPS project, especially if our unregistered member intends to help us out for a month or more. It makes plenty of sense as a stress test for a CPU or a bus controller.

OP, we encourage you to do a little testing with your computer....and welcome any GIMPS results it may produce.

LaurV · 2012-02-12, 07:40

@Christenson: you are right here, sorry. I only saw my interest :D
The advice to use the benchmark option for few tests still stands.

Christenson · 2012-02-15, 02:39

Quote:

Originally Posted by LaurV

@Christenson: you are right here, sorry. I only saw my interest :D
The advice to use the benchmark option for few tests still stands.

Indeed...I second your advice. Thanks.

2012-02-11, 07:10	#1
Unregistered 2·41·53 Posts	help! Can I get the prime95 to test 1 number with all cores at the same time? if so, how?

2012-02-11, 16:25	#3
bcp19 Oct 2011 1247₈ Posts	To use multiple cores on a single exponent, click Test, then select Worker Windows. On the scrteen that pops up, set number of Worker Windows to run to 1 and then set CPUs to use to however many cores you have. Last fiddled with by bcp19 on 2012-02-11 at 16:25

2012-02-11, 11:46	#2
LaurV Romulan Interpreter Jun 2011 Thailand 22700₈ Posts	You can, but it does not make too much sense. For a 4-cores or a 6-cores intel, adding more then 3 cores to the same exponent, generally does not improve the timing, as exchanging data become costly, if you fragment the task too much you spend time putting it together again. To see the results for your computer, use Options/Benchmark from p95's menu and think about the best combination for your computer. Then play with the number of cores and multitrthreading on Test/Workers menu.

2012-02-12, 07:40	#5
LaurV Romulan Interpreter Jun 2011 Thailand 2⁶·151 Posts	@Christenson: you are right here, sorry. I only saw my interest :D The advice to use the benchmark option for few tests still stands.