P-1 factoring Stage 2

dlsilver06 · 2021-08-01, 00:53

I tried going into the "P-1 factoring Q&A" thread first, but it is closed.

Was doing PRP of M113000000 range. Completed running P-1 stage 1 with B1=749000 and B2=16507000, then ran Stage 1 GCD which completed, followed by error message "Insufficient memory to ever run Stage 2." Program then ran Stage 2 GCD (completing in ~124 sec) and has now started PRP test.

I checked my memory settings (Options/Resource limits/advanced), and both daytime and nighttime were set at 0.3GB (although I'm not sure why, as I have 4GM RAM and am running only Prime95). I've now updated those to 2GB day and 2.5GB night.

Question: is it possible or desirable to go back and restart/finish stage 2 P-1? If so, how?

Prime95 · 2021-08-01, 01:44

Unless you happened to have a recent save file (from an automated backup) it is not worthwhile to run stage 2 as prime95 will have to rerun stage 1 from scratch.

The default of 0.3GB is low so that new users don't install prime95 on a machine and unintentionally slow the machine down due to applications lacking sufficient memory.

BTW, welcome to GIMPS!

dlsilver06 · 2021-08-01, 06:04

Thanks--have been with GIMPS for some time, but forgot to update the memory settings on "Older" computer. My bad.

Certainly don't want to re-run Stage 1!

2021-08-01, 00:53	#1
dlsilver06 Apr 2020 3² Posts	P-1 factoring Stage 2 I tried going into the "P-1 factoring Q&A" thread first, but it is closed. Was doing PRP of M113000000 range. Completed running P-1 stage 1 with B1=749000 and B2=16507000, then ran Stage 1 GCD which completed, followed by error message "Insufficient memory to ever run Stage 2." Program then ran Stage 2 GCD (completing in ~124 sec) and has now started PRP test. I checked my memory settings (Options/Resource limits/advanced), and both daytime and nighttime were set at 0.3GB (although I'm not sure why, as I have 4GM RAM and am running only Prime95). I've now updated those to 2GB day and 2.5GB night. Question: is it possible or desirable to go back and restart/finish stage 2 P-1? If so, how?

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2021-08-01, 01:44	#2
Prime95 P90 years forever! Aug 2002 Yeehaw, FL 7³×23 Posts	Unless you happened to have a recent save file (from an automated backup) it is not worthwhile to run stage 2 as prime95 will have to rerun stage 1 from scratch. The default of 0.3GB is low so that new users don't install prime95 on a machine and unintentionally slow the machine down due to applications lacking sufficient memory. BTW, welcome to GIMPS!

2021-08-01, 06:04	#3
dlsilver06 Apr 2020 11₈ Posts	Thanks--have been with GIMPS for some time, but forgot to update the memory settings on "Older" computer. My bad. Certainly don't want to re-run Stage 1!