On Monday 10 March 2003 07:49, Daran wrote: > > B1 and B2 are supposed to be chosen by the client so that the cost/benefit > ratio is optimal. Does this mean that P4s is choose B2 values which are > too high? Or does everything else choose values too low? Or is there some > reason I can't think of, why higher values might be appropriate for a P4?
George? > > In fact, I'm not even sure it does get a higher B2 - the apparent > difference could be, as Brian suggested, due to differences between > versions. I don't have access to a P4, so I can do any testing, But I'd > appreciate it if you or someone else could try starting a P-1 on the same > exponent (not in one of the ranges where it would get a different FFT > length) on two different machines, with the same memory allowed. You would > not need to complete the runs. You could abort the tests as soon as > they've reported their chosen limits. I just tried Test=8907359,64,0 on two systems - an Athlon XP 1700+ and a P4-2533, both running mprime v23.2 with 384 MB memory configured (out of 512 MB total in the system). These were fresh installations, I did nothing apart from adding SelfTest448Passed=1 to local.ini to save running the selftest. The Athlon system picked B1=105000, B2=1995000 whilst the P4 picked B1=105000, B2=2126250. So it seems that P4 is picking a significantly but not grossly higher B2 value. Yes, I checked, both systems are using 448K run length for this exponent (though it's only just under the P4 crossover). Regards Brian Beesley > > > Would I unreserve all the exponents that are already P-1 complete? > > If I don't change the DoubleCheck into Pfactor then couldn't I just let > > the exponent run and then sometime after P-1 is done move the entry and > > the 2 tmp files over to another machine to finish it off? > > If you're going to feed your other machines from this one, then obviously > you won't need to unreserve the exponents they need. But there's an easier > way to do this. Put SequentialWorkToDo=0 in prime.ini, then, so long as it > never runs out of P-1 work to do, it will never start a first-time or > doublecheck LL, and there will be no temporary files to move. I also > suggest putting SkipTrialFactoring=1 in prime.ini. > > > That sounds like more work than I care to do... > > I agree that with 20 boxes, the work would be onerous. > > > ...I can see having 1 machine > > do P-1 on lots of double-checks. > > That would be well worth it. Since one box will *easily* feed the other > twenty or so, you will have to decide whether to unreserve the exponents > you P-1 beyond your needs, or occasionally let that box test (or start > testing) one. > > You may find a better match between your rate of production of P-1 complete > exponents, and your rate of consumption, if you do first-time testing. > > [...] > > > As an mprime user I edit the local.ini file all the time. Per your notes > > I upped *Memory to 466. > > That will certainly help exponents below 9071000 on a P3, or 8908000 on a > P4. The current DC level is now over 9170000, so I doubt this will help > much, (though of course, it won't harm, either). I haven't tried. I'm > still getting enough sub 9071000 expiries. > > > -- > > [EMAIL PROTECTED] - HMC UNIX Systems Manager > > Daran G. > _________________________________________________________________________ > Unsubscribe & list info -- http://www.ndatech.com/mersenne/signup.htm > Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers _________________________________________________________________________ Unsubscribe & list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
