Delivered-To: luke@ndatech.com X-Sender: rugeley@pop3.demon.co.uk X-Mailer: QUALCOMM Windows Eudora Version 5.1 Date: Sat, 15 Dec 2001 22:45:18 +0000 To: Luke Welsh From: mersenne-digest-invalid-reply-address@base.com (Mersenne Digest) (by way of Gordon Spence ) Subject: Mersenne Digest V1 #916 Mersenne Digest Friday, December 7 2001 Volume 01 : Number 916 ---------------------------------------------------------------------- Date: Thu, 6 Dec 2001 10:11:40 -0800 From: "John R Pierce" Subject: Mersenne: silicon valley 'prime' dinner one more time, I'm offering a ride to anyone and everyone who wants to be picked up in the santa cruz or los gatos areas, leaving santa cruz around 5pm friday... I've got a brand new 7 passenger full sized van (Ford E150 'Traveler'), and 7 *is* a Mersenne prime number (2^3 - 1)... anyone wants a ride, email me by mid afternoon tomorrow at this address... - -jrp _________________________________________________________________________ Unsubscribe & list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------------------------------ Date: Thu, 6 Dec 2001 18:50:04 -0000 From: bjb@bbhvig.uklinux.net Subject: Re: Mersenne: New exponents On 5 Dec 2001, at 21:23, Nathan Russell wrote: > However, when the client does contact the server (every 28 days by default, > IIRC), will it not get an "this assignment does not belong to us"? > But the test will continue if it is underway. If it isn't the first entry in worktodo.ini the result will be that the entry is removed by the program when PrimeNet signals this back. > I know that I had that happen while I had QA and primenet work queued on > the same machine, and in fact it happened often enough to be rather annoying. QA is different - if the exponent is in currently active PrimeNet ranges you're stuffed, because PrimeNet can only cope with one person "owning" an exponent at a time & QA runs execute in parallel, whilst PrimeNet will completely disown exponents outside its current active ranges. I run QA assignments with PrimeNet comms disabled. Regards Brian Beesley _________________________________________________________________________ Unsubscribe & list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------------------------------ Date: Thu, 6 Dec 2001 18:50:04 -0000 From: bjb@bbhvig.uklinux.net Subject: Re: Mersenne: New exponents On 5 Dec 2001, at 22:33, George Woltman wrote: > > > No. The server never contacts the client. That's too much of a security > > > risk in my book. Correct. Though I suppose the server could automatically e-mail a warning to the user that their assignment has been pre-empted. > > > >That isn't exactly what I meant. Given that his exponent has been expired > >and assigned to me, if he then checks in later to report further progress > >on the exponent, will the server tell his client that the exponent has > >been expired and assigned to someone else, or will it tell me the next > >time I check in that he is still working on it? Surely _his_ checkin will result in "assignment does not belong to you" if he's allowed it to expire? > > If he checks in his result, primenet will return error 11 - but your > computation > will continue. > > >Or do both of our clients continue happily chugging away on it? > > I think prime95 removes it from worktodo.ini only if you have not > started the LL test. This makes sense... > > Obviously there is some room for improvement here. The current scheme > works OK for first time checks since yours would then become a valid > double-check. There are four points here: (1) there's a Big Difference between abandoning a run which is only just started and one which is nearly complete; (2) if you do decide to change the policy to "abandon", it would be wise to make the program keep the savefile (can be deleted manually if neccessary) just in case the residuals don't match - it seems silly to throw away work done already when it still might be required; (3) IMO the occasional triple check doesn't matter; (4) AFAIK it is fairly rare for people who allow assignments to expire _having made at least one intermediate checkin_ to later reappear with a result. The current policy is fine, even ideal, so far as "first LL test" assignments are concerned. I'm not convinced that changing the policy for DC assignments would result in a noticeable improvement in the efficiency of the project as a whole. Regards Brian Beesley _________________________________________________________________________ Unsubscribe & list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------------------------------ Date: Thu, 06 Dec 2001 17:26:06 -0500 From: Paradox Subject: Mersenne: But....but...when is 3^x - 2 prime? I've got two questions: 1) I have a P4 1.9 GHz with PC800 ram that is testing an exponent in the 333XXXXX range, and it is getting approximately 0.180 sec/iteration when completely idle on Windows 2000. According to the benchmark on mersenne.org, it should be around 0.143. Am I losing cycles somewhere? Is it possible the mainboard (Intel 850GBC) is lying to me about the clockspeed? (btw, Intel's monitor says the CPU temperature is fine) 2) I have an old PII 300 MHz that appears to have become roasted. When I turn it on after it is off for a period of time, it stalls in the memory check (64 MB). When I reset it, it boots into Windows 2000, but it is dangerously unstable. It stalls often and pixel chunks on the screen sometimes spontaneously change. When I run prime95, it complains usually within a few minutes about SUMINP != SUMOUT or rounding errors. The strange thing is that sometimes I can run the stress tester for 7 to 8 hours at a time without problems, assuming I don't touch the machine. (Although it seems to be getting worse.. it will just freeze up by itself now). So the question...does this sound like a memory problem, a CPU problem, or a mainboard problem? How can I determine exactly? Can it be saved? BTW, the subject of this message has nothing to do with the contents. But its an interesting problem, I guess. When is a^x - a + 1 prime? (did I mention that 3^957 - 2 is prime?) Regards, PdoX (paradox3@maine.rr.com) _________________________________________________________________________ Unsubscribe & list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------------------------------ Date: Thu, 06 Dec 2001 17:08:19 -0500 From: Jud McCranie Subject: Re: Mersenne: But....but...when is 3^x - 2 prime? At 05:26 PM 12/6/2001 -0500, Paradox wrote: >1) I have a P4 1.9 GHz with PC800 ram that is testing an exponent in the >333XXXXX range, >and it is getting approximately 0.180 sec/iteration when completely idle >on Windows 2000. >According to the benchmark on mersenne.org, it should be around 0.143. >Am I losing cycles >somewhere? Is it possible the mainboard (Intel 850GBC) is lying to me >about the clockspeed? Do you have an actual video card or is the video on the motherboard (sharing memory)? That can be a factor. +---------------------------------------------------------+ | Jud McCranie | | | | Programming Achieved with Structure, Clarity, And Logic | +---------------------------------------------------------+ _________________________________________________________________________ Unsubscribe & list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------------------------------ Date: Thu, 06 Dec 2001 17:25:15 -0500 From: Nathan Russell Subject: Re: Mersenne: But....but...when is 3^x - 2 prime? At 05:26 PM 12/6/2001 -0500, Paradox wrote: >1) I have a P4 1.9 GHz with PC800 ram that is testing an exponent in the >333XXXXX range, >and it is getting approximately 0.180 sec/iteration when completely idle >on Windows 2000. >According to the benchmark on mersenne.org, it should be around 0.143. I don't know much about the P4. That said, there's a few possibilities that come to mind. 1. A screensaver could be using some CPU time. 2. Indexing service, virus scanning software, or something else may be set to start itself when the system is 'completely idle'. I doubt it's indexing service - not with that great a reduction. 3. The motherboard may be less than ideal in any of a number of ways. Nathan _________________________________________________________________________ Unsubscribe & list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------------------------------ Date: Thu, 06 Dec 2001 16:43:18 -0800 From: Luke Welsh Subject: Mersenne: Un nuovo numero primo di Mersenne Dated December 4: http://www.lescienze.it/index.php3?id=4383 _________________________________________________________________________ Unsubscribe & list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------------------------------ Date: Fri, 7 Dec 2001 00:50:07 -0000 From: "Daran" Subject: Re: Mersenne: More on M#39 - ----- Original Message ----- From: "George Woltman" To: Sent: Thursday, December 06, 2001 4:50 PM Subject: Mersenne: More on M#39 > I presume Scott will now try get the story really rolling in the press. > Let's wish him luck. Can you let us know when we can start doing our bit to promote this. I'm itching to get this into into my email/newsgroup sig, but I don't want to preempt the official release by as much as one second. Also what's the prefered URL? > Congratulations to all, > George Daran G. _________________________________________________________________________ Unsubscribe & list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------------------------------ Date: Thu, 06 Dec 2001 20:16:36 -0500 From: Nathan Russell Subject: Re: Mersenne: More on M#39 At 12:50 AM 12/7/2001 +0000, Daran wrote: >----- Original Message ----- >From: "George Woltman" >To: >Sent: Thursday, December 06, 2001 4:50 PM >Subject: Mersenne: More on M#39 > > > > I presume Scott will now try get the story really rolling in the press. > > Let's wish him luck. > >Can you let us know when we can start doing our bit to promote this. I'm >itching to get this into into my email/newsgroup sig, but I don't want to >preempt the official release by as much as one second. It looks like it's more or less official now... look at the GIMPS webpage's header, and then look at the status page. Nathan _________________________________________________________________________ Unsubscribe & list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------------------------------ Date: Fri, 07 Dec 2001 14:05:40 +0100 From: Alexander Kruppa Subject: Mersenne: 39. Mersenne-Primzahl entdeckt There is an _excellent_ article on the Heise Newsticker (in german). This is one of the few I've seen that has all the facts right and it gives a little extra info, too (i.e. it mentions Crandall's new book, Prime Numbers, as a source for info on the DWT). Worthwhile to check out if you read german. http://www.heise.de/newsticker/data/as-06.12.01-000/ Now that the news is official, a big CONGRATS to Michael, George, Scott and all Mersenne hunters out there. Steve Harris and I will meet in Munich tonight and have a "Prost!!" to the new prime. 6pm pacific time is 1am MET - let's see if we can stay up to sync with the California crowd for a toast! Alex _________________________________________________________________________ Unsubscribe & list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------------------------------ Date: Fri, 7 Dec 2001 12:56:49 -0800 From: "John R Pierce" Subject: Mersenne: last call for a santa cruz ride... (was: silicon valley 'prime' dinner) > one more time, I'm offering a ride to anyone and everyone who wants to be > picked up in the santa cruz or los gatos areas, leaving santa cruz around > 5pm friday... I've got a brand new 7 passenger full sized van (Ford E150 > 'Traveler'), and 7 *is* a Mersenne prime number (2^3 - 1)... > > anyone wants a ride, email me by mid afternoon tomorrow at this address... is *anyone* going to this dinner? I still plan to launch from Santa Cruz around 5pm, and my ride offer is still valid. I could also stop and pick folks up in the Los Gatos area, I guess. Planned route is 17->85->Mtn View... - -jrp (primenet #78 or so) _________________________________________________________________________ Unsubscribe & list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------------------------------ End of Mersenne Digest V1 #916 ******************************