----- Original Message ----- From: "Gerry Snyder" <[EMAIL PROTECTED]> To: "mer" <[EMAIL PROTECTED]> Sent: Monday, January 14, 2002 5:37 AM Subject: Mersenne: Optimizing P4 usage
>At home I have 2 PC's, both of which devote their spare cycles to GIMPS. >One is a 1.3 GHz P4 running W98, and the other a dual 1 GHz P3 running >linux. One of the P3's is doing LL testing, and the other is doing >mostly ECM, with a little trial factoring thrown in. If I'm not mistaken, you'd be better to have one of your dual processors doing just TF. [...] > My question is whether it is worth the trouble to shift the trial and > P-1 factoring of the next one to one of the P3 processors (the non-LL > one). It might lead to one extra LL test in two years. Definitely move the TF to your P3. A P4 doing integer work is wasted. > The worktodo file for the P4 has: > > Test=current,68,0 Why hasn't your current assignment had a P-1? You should suspend testing to do this. My system with 459MB available memory would choose B1=375000, B2=8156250 (5.17% chance of success) for a 33M first-time assignment (i.e a successful P-1 saves two LL tests) and B1=180000, B2=2970000 (3.78%) for a 33M doublecheck assignment. Your system - with a different amount of available memory - might choose different limits, but whatever they are, you should choose limits somewhere between them, closer to the first-time, or doublecheck values according to how far through the first time check you are. > Test=next,60,0 > > It should be noted that the W95 machine does not have enough RAM for > phase 2 of the P-1 factoring, but the linux machine does. Do P-1 on whichever machine can give it the most memory, and always give it as much as you can. 340MB or thereabouts is optimal for a 6-7M exponant. GOK how much a 33M exponant would take. > Any suggestions? If you've got less than 512MB on your linux box, email the exponant(s) to me, (after you've TFed it) and I'll P-1 it for you. I can do a 6-7M P-1 in about 3 hours, so I'd guess it'd take a couple of days. > TIA, Gerry Daran G. _________________________________________________________________________ Unsubscribe & list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
