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Old 2015-12-03, 20:20   #1
tha
 
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Default mprime checking available memory

I installed 4GB in a machine and configured mprime to use 3072 of it. I then replaced the 4GB with 2GB and forgot to reconfigure mprime. Oddly mprime keeps on running and does not seem to notice the total amount has changed. It starts the second stage of P-1 work with the parameters that you would expect for 4GB, and does not protest along the way.
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Old 2015-12-03, 22:00   #2
chalsall
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Quote:
Originally Posted by tha View Post
It starts the second stage of P-1 work with the parameters that you would expect for 4GB, and does not protest along the way.
Can anyone say "swap" or "thrash"?
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Old 2015-12-04, 02:43   #3
Madpoo
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Quote:
Originally Posted by chalsall View Post
Can anyone say "swap" or "thrash"?
Although, it depends on the work being done and how much actual RAM mprime needs.

I'd want to know what exponent and what bounds were being used, then see exactly how much memory that process is snarfing up.

If it is more than the free RAM, yeah, thrashing is an understatement. Seems like it would beat your system within an inch of it's life.
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Old 2015-12-04, 03:05   #4
Prime95
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Looking at the source code: mprime will ask the OS for the amount of physical ram. If your day or night mem settings are greater than the amount of physical RAM, then that setting is reduced to "physical RAM - 8MB".

Of course, I imagine this would still thrash.

I cannot explain why the P-1 stage 2 bounds would be unaffected.
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Old 2015-12-04, 12:35   #5
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the only thought that came to my mind is that with multiple channels 2GB could equate to more than 4GB.
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Old 2015-12-04, 16:48   #6
Dubslow
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Quote:
Originally Posted by science_man_88 View Post
the only thought that came to my mind is that with multiple channels 2GB could equate to more than 4GB.
Are you serious?
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Old 2015-12-04, 18:11   #7
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Quote:
Originally Posted by Dubslow View Post
Are you serious?
I didn't say I was smart at these things
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Old 2015-12-07, 15:56   #8
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I think you have to test the performance of your computer ...
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