Two programs on same machine?

2004-01-31, 00:10

I run Prime95 on two computers at home and one of the computers crashed. On the other one I have two partitions (one is FAT32 and another is NTFS). Can I copy the whole Prime95 folder from the wasted computer onto the second drive of the alive one and pretend it is the old machine (at least until I revive the dead one)? Thanks.

PrimeCruncher · 2004-01-31, 01:32

Unless the machine is dual-processor, I don't recommend it. The two Prime95 instances would conflict with each other. You can set them at the same priority to counteract this but then each instance will effectively run at half-speed. The wiser course is to add the exponents from the wasted machine to your worktodo.ini file. If this makes the work queue too long Prime95 will automatically unreserve some exponents.

2004-01-31, 02:28

Quote:

Originally Posted by PrimeCruncher

The wiser course is to add the exponents from the wasted machine to your worktodo.ini file.

Thank you.

PrimeCruncher · 2004-01-31, 03:10

No problemo. That's what this forum is for.

patrik · 2004-01-31, 12:27

Also copy the save file. If you are doing a Lucas-Lehmer test, the save file is called something like pXXXXXXX. Otherwise it will start that exponent from the beginning.

But I don't think there would be much harm of running two instances of Prime95. They would run at 50% each, not much less. Just be sure (if you are doing P-1) that the memory settings are low enough for allowing running two P-1 tests at the same time.

PrimeCruncher · 2004-01-31, 15:29

Quote:

Originally Posted by patrik

Also copy the save file. If you are doing a Lucas-Lehmer test, the save file is called something like pXXXXXXX. Otherwise it will start that exponent from the beginning.

Ooh, yeah, I forgot about that.

Quote:

Originally Posted by patrik

But I don't think there would be much harm of running two instances of Prime95. They would run at 50% each, not much less. Just be sure (if you are doing P-1) that the memory settings are low enough for allowing running two P-1 tests at the same time.

Well, what's the point? Either you can run two Prime95 instances at half-speed or one at full-speed. The same amount of work will get done.

ET_ · 2004-01-31, 15:41

Quote:

Originally Posted by PrimeCruncher

Well, what's the point? Either you can run two Prime95 instances at half-speed or one at full-speed. The same amount of work will get done.

AFAIK, Prime95 is coded to get full use of the pipeline, cache and registers of the processor. Two instances of the same program would impose a delay due to context switching, cache misses and wait cycles for the pipeline to empty...

Luigi

outlnder · 2004-01-31, 18:47

Sometimes when copying the pxxxxxxxx file, the computer will give it an extension, such as ".dat". You will need to rename the file after moving it, eliminating the ".dat".

jinydu · 2004-02-01, 02:09

Is it possible to view the pxxxxxxxx file at all?

Xyzzy · 2004-02-01, 02:13

Quote:

Originally Posted by jinydu

Is it possible to view the pxxxxxxxx file at all?

Yes, but it looks like garbage because it is a binary file... You can use "od" to dump the file in Linux... I suppose in Windows you would need some sort of hex editor or something...

Pablo the Duck · 2004-02-01, 05:51

Quote:

Originally Posted by jinydu

Is it possible to view the pxxxxxxxx file at all?

Sometimes you can even listen to it! Nautilus (a Linux GUI file manager) once mistakenly identified a pxxxxxxxx file as an MP3 and, when I clicked on it, it played a scratching noise followed by an ear splitting popping sound.

2004-01-31, 00:10	#1
Unregistered 2²×17×97 Posts	Two programs on same machine? I run Prime95 on two computers at home and one of the computers crashed. On the other one I have two partitions (one is FAT32 and another is NTFS). Can I copy the whole Prime95 folder from the wasted computer onto the second drive of the alive one and pretend it is the old machine (at least until I revive the dead one)? Thanks.

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2004-01-31, 01:32	#2
PrimeCruncher Sep 2003 Borg HQ, Delta Quadrant 2·3³·13 Posts	Unless the machine is dual-processor, I don't recommend it. The two Prime95 instances would conflict with each other. You can set them at the same priority to counteract this but then each instance will effectively run at half-speed. The wiser course is to add the exponents from the wasted machine to your worktodo.ini file. If this makes the work queue too long Prime95 will automatically unreserve some exponents.

2004-01-31, 03:10	#4
PrimeCruncher Sep 2003 Borg HQ, Delta Quadrant 2×3³×13 Posts	No problemo. That's what this forum is for.

2004-01-31, 12:27	#5
patrik "Patrik Johansson" Aug 2002 Uppsala, Sweden 5²·17 Posts	Also copy the save file. If you are doing a Lucas-Lehmer test, the save file is called something like pXXXXXXX. Otherwise it will start that exponent from the beginning. But I don't think there would be much harm of running two instances of Prime95. They would run at 50% each, not much less. Just be sure (if you are doing P-1) that the memory settings are low enough for allowing running two P-1 tests at the same time.

2004-01-31, 18:47	#8
outlnder Aug 2002 2·3·53 Posts	Sometimes when copying the pxxxxxxxx file, the computer will give it an extension, such as ".dat". You will need to rename the file after moving it, eliminating the ".dat".

2004-02-01, 02:09	#9
jinydu Dec 2003 Hopefully Near M48 1758₁₀ Posts	Is it possible to view the pxxxxxxxx file at all?