Prime95 version 29.4

[Prime95]

Originally Posted by Falkentyne

Hello, I have been unable to get AVX2 support to work in the latest prime95 or even earlier versions. Defaults to FMA3.

This is normal. FMA3 is part of AVX2, in fact it is the only AVX2 instruction that prime95 uses.

[ixfd64]

I have a possible bug report and a suggestion.

1. I've noticed that save files are not automatically deleted when the user completes an assignment started via the Advanced menu. This is true for at least P-1 assignments. Is this intentional?

2. I prefer that the automatic benchmark data do not clutter up my results.txt file. Could we get the option to dump the data to another file instead? I could manually split my results.txt file but am not sure if Prime95 relies on results.txt to get the benchmark data it needs.

[James Heinrich]

If I recall, it was intentional to not delete P-1 saves to allow easy continuation to higher bounds (e.g. if no [new] factor was found).
I would also prefer to see benchmarks split to benchmarks.txt or similar instead of cluttering up results.txt

[Prime95]

Originally Posted by ixfd64

I prefer that the automatic benchmark data do not clutter up my results.txt file. Could we get the option to dump the data to another file instead? I could manually split my results.txt file but am not sure if Prime95 relies on results.txt to get the benchmark data it needs.

I'll add that to my todo list for the next release.

Prime95 does not read benchmark data stored in results.txt -- it is safe to delete it or move it to a separate file.

[Prime95]

Originally Posted by Prime95

This is normal. FMA3 is part of AVX2, in fact it is the only AVX2 instruction that prime95 uses.

Correction. Some trial factoring code can use other AVX2 instructions. This does not affect stress testing.

[ixfd64]

Originally Posted by Prime95

Prime95 does not read benchmark data stored in results.txt -- it is safe to delete it or move it to a separate file.

Thanks for the information. I've split my results.txt file - it looks a lot cleaner now!

[DRMEDESY]

Hi, I installed today version 29.4 build 8 on my Debian Linux machine and I wanted to set it to run in mode 154. However it just told me that this mode is invalid:

[Comm thread Mar 26 14:26] RESPONSE:
[Comm thread Mar 26 14:26] pnErrorResult=0
[Comm thread Mar 26 14:26] pnErrorDetail=Invalid work preference: 154. Using de fault work preference instead.
[Comm thread Mar 26 14:26] Server assigned Lucas Lehmer primality double-check w ork.

Any suggestions? In the prime.txt I can see that the work preference is set to 154.

[ATH]

There is no work preference 154.

0 - Whatever makes the most sense
1 - Trial factoring to low limits
2 - Trial factoring
4 - P-1 factoring
5 - ECM for first factor on Mersenne numbers
6 - ECM on Fermat numbers
8 - ECM on mersenne cofactors
100 - First time primality tests
101 - Double-checking
102 - World record primality tests
104 - 100M digit number to LL test (not recommended)
150 - First time PRP tests (Gerbicz)
151 - Doublecheck PRP tests (Gerbicz)
152 - World record sized numbers to PRP test (Gerbicz)
153 - 100M digit number to PRP test (Gerbicz)
160 - PRP on Mersenne cofactors
161 - PRP double-checks on Mersenne cofactors

[Mysticial]

Originally Posted by Prime95

This is normal. FMA3 is part of AVX2, in fact it is the only AVX2 instruction that prime95 uses.

The VIA Isiah C4650 supports AVX and AVX2. But not FMA3.

Not that anybody will actually use that processor for prime though...

[DRMEDESY]

Hi ATH,
my menu looks different. This is the one of my version:

Use the following values to select a work type:
0 - Whatever makes the most sense
100 - First time LL tests
102 - World record LL tests
101 - Double-check LL tests
150 - First time PRP tests
152 - World record PRP tests
151 - Double-check PRP tests
2 - Trial factoring
4 - P-1 factoring
154 - 100 million digit PRP tests
104 - 100 million digit LL tests (not recommended)
160 - First time PRP on Mersenne cofactors
161 - Double-check PRP on Mersenne cofactors
5 - ECM for first factors of Mersenne numbers
8 - ECM on Mersenne cofactors
6 - ECM on Fermat numbers
1 - Trial factoring to low limits

It tells me that there is no 153, but a 154 instead....

[Prime95]

That's a bug in the linux menus. Change your work preference to 153 and all should be good.