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Old 2005-06-15, 23:44   #1

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Default mprime takes a lot cpu usage

im totally new to this prime hunting =)
but i read that mprime shouldn't take so much cpu, that is it low priorety
But when i run it, it use most cpu, which makes my computer run slower..

i have a athlon 2500+ so i don't think that should be a problem?

is this normal or is something wrong?

i want to add a question,
in the worktodo.ini list i found:

but what does this mean...
i understand that its a number, but it would be fun to know how it looks like...
do you understand the question?

Last fiddled with by d4n1el on 2005-06-15 at 23:48
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Old 2005-06-16, 00:59   #2
db597's Avatar
Jan 2003

3138 Posts

That is perfectly normal. It is true that Prime95 runs at low priority. So it will only use spare CPU cycles, and not interfere with normal programs. However, this doesn't mean that it is not CPU intensive. Prime95 will use every single spare CPU cycle available, until the CPU is 100% utilised.

So for example, if you are running Photoshop, and it is taking 2% of the CPU, this means that the remaining 98% will be spare cycles. This 98% will then be taken by Prime95!

If you start doing some intensive work, and photoshop starts to require say 80% of the CPU, then only 20% will be spare cycles, and Prime95 will get only 20% of the CPU.

The Prime95 only gets "what's left", but it will use up all of the remainder.

As for Test=28883749,68,0 - this means that you are running LL tests on exponent 28883749. The 68 is the number of bits used for trial factoring, and 0 means that the P-1 factoring stage is not yet done. I suggest not editing this file (in case you end up doing work on an exponent that someone else has already been assigned).
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Old 2005-06-16, 02:21   #3
dsouza123's Avatar
Sep 2002

2·331 Posts

The number is 2^28883749 - 1 ( 2 to the 28883749 power then minus 1)
In binary it is 28883749 ones.

A small example 2^7 - 1 is 127 or 1111111 in binary.

The slowdown isn't a normal condition.
High CPU usage is normal, about 95+ %.

What program(s) are running slower ?

How much RAM is in the PC ?
Is the harddrive constantly in use ?
(The harddrive light stays on, may even be able to hear it.)
If so virtual memory is being swapped to disk,
it is a result of not enough RAM for all the programs running.

Last fiddled with by dsouza123 on 2005-06-16 at 02:28
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