Re: Mersenne: searching the biggies 2
Nathan Russell wrote: > Last time I checked, there were two universtites (labeled as such that is) > at the top of the list but no companies really near the top. Ja, however if someone manages to get a realy big company to play, there might be some very good reasons to *not* show up in the top contributors list. In fact, the someone who organized and pushed thru the effort might even want to conceal her own efforts in that direction. spike _ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
Re: Mersenne: searching the biggies
>From: Jukka Tapani Santala <[EMAIL PROTECTED]> >To: Nathan Russell <[EMAIL PROTECTED]> >CC: [EMAIL PROTECTED] >Subject: Re: Mersenne: searching the biggies >Date: Sat, 4 Mar 2000 01:19:56 +0200 (EET) > >On Fri, 3 Mar 2000, Nathan Russell wrote: > > >>Two of their other projects lost GIMPS-years of work each because of > > >>stupid bugs and I got fed up and left. > > >Uh... we had a bug too. Ironically, it was announced on April Fools >Day > > >last year. That caused quite a stir. We lost roughly a GIMPS month of > > >work. > > I am aware that there was a bug in V 17. There will always be bugs. >The > > bugs (plural) that occured in my former project were merely the final >reason > > that I decided to leave. > >Incidentally, what bothers me about the "other project" is not that they >had bugs, but more that the explanations of the bugs don't seem to check >up(*), to such a degree as they bother to even state what the issues >were. In fact they had a third, similiar incident involving the suspected >delay in announcing the finishing of one competition long back, altough I >don't remember/know enough details to comment other than that to note they >do certainly seem to have a history of this sort of stuff cropping >up. Incidentally, could you imagine them having a "Make noise if correct >solution found?" option in their clients... ;) Not in, um, about as long as it would take to test MM(127)! > >(*) For the most recent problem... As far as I can tell, when switching >between systems - even between OS'es on the same computer - the involved >client versions would happily restart the current work unit losing all >work so far. The announcement about the bug claimed it would only occur in >such a situation, which thus should not happen. > >To further confuse issues, the announcement claims that they have to >abandon all work so far because the faulty packets are undetectable, and >that the problem generating the faulty packets has been fixed, but in >practically same breath continues that servers have been made to reject >the faulty packets... Which should be both non-existent and impossible to >spot? That is quite an interesting question. > >And exactly how does incorrect count of possible solutions in a >pre-defined block invalidate the results, anyway? I think OGR could be one >of the most useful applications distributed computing has been applied to >so far, but unfortunately I can't feel comfortable my CPU-ticks go towards >what I want and I am getting full disclosure with who are running it now. It seems to me that they must have had an issue with some aspect of the client that they are unwilling to publically discuss. Perhaps the issue that occured couldn't be described without giving away vital info about their verification code. Even if that were the case, however, one would think that they would merely say so, or even a simple "We found a bug, wait for a new version to come out" rather than lying to everyone. > > >Incidentally, have you seen JETI@home? Unfortunately I don't remewmber the >URL right now, but that's worth checking out, too, at least if you don't >take everything related to distributed computing too seriously ;) I thought it was YETI@home > >Incidentally#2, has anybody looked into the application of distributed >computing into genetics? With the increased availability of genetic >information online, on the WWW, such applications don't seem too >far-fetched. Sounds like a neat field... > >Anyway, sorry to sound out, but I am feeling rather incensed by the way I >perceive many distributed computing operations to disrespect/waste their >contributors and the resources. Words seem to fail me in correctly >describing it just now, but I hope you can see what I mean. I think the >least Distributed Computing outfits "owe" to their contributors is a clean >accounting of what their CPU-time has went towards. I happen to know that SETI duplicates their work two or three times, for example Nathan > > -Donwulff > __ Get Your Private, Free Email at http://www.hotmail.com _ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
Re: Mersenne: searching the biggies
>From: George Woltman <[EMAIL PROTECTED]> >To: "Nathan Russell" <[EMAIL PROTECTED]> >Subject: Re: Mersenne: searching the biggies >Date: Fri, 03 Mar 2000 16:32:10 -0500 > >Hi, > >>I don't honestly think I would have the patience to run 10 M tests, > >Me too. 1 year for a 1 in 250,000 chance - no thanks. I've had a computer >do ECM factoring for a year just for some variety. > >Regards, >George > I sympathize. I just set my 'work to cache' value up by two weeks and got a batch of factoring assignments, just for variety. I shut my program down and re-organized the worktodo file so those were interspersed with the tests, for variety's sake. I checked all the carriage returns and stuff before I saved it and started the client; was there any risk in doing that? I have Gateway Goback (A program that constantly saves about 500 meg of the most recent versions of changed files) so I can undo it if need be. Nathan __ Get Your Private, Free Email at http://www.hotmail.com _ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
Mersenne: Re: Security and Prime95/mprime
On Fri, Mar 03, 2000 at 04:46:30AM -0800, Paul Leyland wrote: >George is an honorable man, I'm sure, and has not knowingly put in any >loopholes. I'm equally sure that he's not infallible and that he will >freely admit to this. Do *you* want to bet the security of your site even >more than you are now doing? Suggestion: Compile mprime from source code. Then you have it all there. Sure, you won't get credit (since the security codes are zeroed out), but you will still contribute to the project. /* Steinar */ -- Homepage: http://members.xoom.com/sneeze/ _ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
Mersenne Digest V1 #701
Mersenne Digest Friday, March 3 2000 Volume 01 : Number 701 -- Date: Wed, 1 Mar 2000 20:40:35 -0800 From: "John R Pierce" <[EMAIL PROTECTED]> Subject: Mersenne: Williamette Hmm. Microprocessor Reports has released some interesting tidbits about the new Williamette processor which will probably be the Pentium-4... This is the chip Intel recently demonstrated running at 1.5GHz. Willamette will be packaged in flip-chip PGA (FC PGA) and was designed for a socket of between 400 and 500 pins, which Intel referred to as Socket-W. The unnamed Willamette bus is a source- synchronous 64-bit 100MHz bus that is quad-pumped to an equivalent of 400MHz per bit, delivering a total of 3.2GB/s of bandwidth--three times the bandwidth of the fastest Pentium III bus. The chip set for Willamette, code-named Tehama, will be a dual-RAC (RDRAM) design. A unique and unexpected aspect of Willamette's microarchitecture is its "double-pumped" ALUs. Claiming the effective performance of four ALUs, the two physical ALUs are each capable of executing an operation in every half-clock cycle. The anticipated improvements to SSE, called SSE2, were introduced in Willamette, including support for (dual) double-precision SIMD floating-point operations. so, its more than just a 1GHz+ P-III design, they've done some significant architectural internal things. And, that double SIMD FPU thing otta rock for LL tests, eh? :D - -jrp _ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Thu, 02 Mar 2000 13:40:55 -0500 From: George Woltman <[EMAIL PROTECTED]> Subject: Re: Mersenne: Williamette Hi, At 08:40 PM 3/1/00 -0800, John R Pierce wrote: >Hmm. Microprocessor Reports has released some interesting tidbits about the >new Williamette processor which will probably be the Pentium-4... This is >the chip Intel recently demonstrated running at 1.5GHz. Intel has info on this processor at http://developer.intel.com/design/processor/wmtsdg.htm The chip has good potential. The new SIMD2 instructions have the potential of doubling throughput. It also looks like FPU operations can be done in parallel with SIMD2 - that's triple the throughput of a PIII. Not to mention running at 1.5GHz! Of course, time will tell as to how good this processor really is. There could be other bottlenecks, it may not be easy to recode prime95 to use the SIMD2 instructions. The latencies for FPU operations are higher than in the P-III. The FXCH instruction is no longer free. Mispredicted branch penalties are higher, etc. etc. I've not heard any rumors as to a release date, but it looks like I'll have to buy two new computers in the next 12 months. An IA-64 and a Willamette! Regards, George _ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Thu, 2 Mar 2000 14:01:24 -0500 (EST) From: "St. Dee" <[EMAIL PROTECTED]> Subject: Mersenne: Security and Prime95/mprime Hi, I'll likely be moving to a cable modem soon and intend to install a machine to act as a firewall, likely a Linux box. Since it will be sitting there all day doing nothing other than screening stuff between my LAN and the 'Net, I thought I'd run mprime (if Linux) on it. Of course, all of the security gurus say to run nothing beyond the programs actually needed on the firewall box. Am I creating any security risks by running mprime on the firewall box? I'm sure some of you must be doing that--noticed any problems? Thanks! Kel Utendorf _ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers -- Date: Thu, 2 Mar 2000 22:36:20 + From: "Steinar H. Gunderson" <[EMAIL PROTECTED]> Subject: Mersenne: Re: Security and Prime95/mprime On Thu, Mar 02, 2000 at 02:01:24PM -0500, St. Dee wrote: >Am I creating any security risks by running mprime on the firewall box? You shouldn't, since mprime doesn't deal with server sockets (only the occasional HTTP traffic to PrimeNet) at all. The only problem I can think of, is that it eats a chunk of your RAM, so a DoS attack would probably be slightly easier (at least if somebody can connect 1 times to your FTP socket, and inetd fires up a new ftpd dæmon for every new socket). I run it on a 486sx/16 (24MB RAM, though) just fine, and that machine serves 3 proxy requests (HTTP) a day :-) /* Steinar */ - -- Homepage: http://members.xoom.com/sneeze/ _ Unsubscribe & list info
Re: Mersenne: searching the biggies
>From: George Woltman <[EMAIL PROTECTED]> >To: "Nathan Russell" <[EMAIL PROTECTED]>,[EMAIL PROTECTED] >Subject: Re: Mersenne: searching the biggies >Date: Fri, 03 Mar 2000 11:39:44 -0500 > >Hi, > >At 11:42 PM 3/2/00 -0500, Nathan Russell wrote: >>>Nathan Russell asked: How much are the people who are trying to >>>find a 10 million digit prime contributing to the search? > >I agree that all machines are contributing to our knowledge of Mersenne >numbers. The gaps will eventually be closed. > >Since you're a relative newbie, the overriding goal of GIMPS has always >been "have fun". That translates into doing the type of work that most >interests you (as long as we all do the work in a coordinated manner). I feel that I appreciate the excitement of doing the first-time tests, and that is why I am chosing to do those. I don't honestly think I would have the patience to run 10 M tests, and if I were in it for the money (which I'm not) I would calculate that the regular tests actually have a higher expected prize yield per time. I actually just got 2 weeks' worth of factoring for myself, just for variety's sake. > >>That is precisely why I switched to GIMPS from another project whose sole >>purpose was to simply recover a cute little, probably political, saying >>that someone had hidden. > >There are those that view prime number hunting as equally useless. I don't >view GIMPS as in competition with other distributed projects. The links at >http://www.mersenne.org let you choose the project that is most appealing >to you. All are worthy in their own way. > That is true. I was stating my own views, and I respect that others may have different motives. >>Two of their other projects lost GIMPS-years of work each because of >>stupid bugs and I got fed up and left. > >Uh... we had a bug too. Ironically, it was announced on April Fools Day >last year. That caused quite a stir. We lost roughly a GIMPS month of >work. I am aware that there was a bug in V 17. There will always be bugs. The bugs (plural) that occured in my former project were merely the final reason that I decided to leave. Nathan > >>This may seem like flamebait, and I do not intend it that way. > >Welcome aboard and good luck with your LL tests - but most importantly... > >Have fun, >George > __ Get Your Private, Free Email at http://www.hotmail.com _ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
Re: Mersenne: Re: How much are the 10 M gamblers contributing?
On 3 Mar 00, at 17:42, Dave Mullen wrote: > Now a number of 10 million decimals is approx. 33 million bits long i.e. > the Prime Exponent would be approx. 33 million. Yes, this is perfectly true. > > And I'm sure some of you have read the theories about the "missing > Mersenne", and the analysis done on the sequence of known Mersenne Primes. > If they turn out to be accurate, then we might be better looking at the 47 > - 49 million Prime Exponent range. Ah, but ... theories being theories ... Suppose you have an object whose colour is such that it appears red until 4th March 2000 but blue from that date onwards. So far, every time you've observed it, it's proved to be red. Past observations are not neccessarily a good predictor of what you will observe tomorrow! No-one seems to seriously doubt that the underlying distribution of Mersenne primes is at least fairly random, and that the density falls off with increasing exponents. So the chance of any particular exponent in the region of 48 million yielding a Mersenne prime is less than the chance of any particular exponent "just big enough" for the Mersenne number to have 10 million digits. To test an exponent around 48 million will take about twice as long; so (given the current state of the art) it looks as though testing the smallest eligible exponents is the better strategy. If you really want to have a go at the 48 million range, fair enough - but please tell someone (George?) so that nobody else wastes time by duplicating work on the same exponents - there are plenty of candidates available!!! > > For interest, has anyone calculated benchmarks, or run LL tests in those > ranges; I guess not many, 8 months is a long time to wait for a result !! The existing v19 program is quite capable of running 10 timed iterations on an arbitary exponent up to at least 79 million. Extrapolation of the full test run time is a simple job, in fact "Advanced/Time" does it for you. No-one has reported any completed LL tests for any "10 million digit" exponent yet; v19 hasn't been out that long, so that even anyone who started on Release Day & has religiously followed the processor speed leapfrog game is probably still some way from completing the first one. > > "And the winning ticket in this year's Christmas Raffle is number > 111.." How many 1's? Regards Brian Beesley _ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
Re: Mersenne: Re: How much are the 10 M gamblers contributing?
>From: "Dave Mullen" <[EMAIL PROTECTED]> >To: <[EMAIL PROTECTED]> >Subject: Mersenne: Re: How much are the 10 M gamblers contributing? >Date: Fri, 3 Mar 2000 17:42:02 +0800 > >Perhaps I'm a little under-speed here ... > >I understood that the $100,000 award was for the first 10 million digit >(that is to say 10 million decimal digit Mersenne Prime). Well, it doesn't have to be a Mersenne prime, but checking an arbitrary prime in a range in which probable primes haven't been shown (by elimination) to all prime inbvolves locating a strong candidate with probable primes and then trying all prime factors up to its square root. For a 10 million digit number, that would be all prime factors up to those of something like 5.1 M digits, which is to say a HUGE number of factors. Thus, the winner will almost certainly be a Mersenne prime, unless the Mersenne primes are shown to be finite in number, in which case we will have to wait until there are computers strong enough to factor arbitrary primes in that size range. I am not sure that factors such as the speed of light and the Hesieberg principal will even permit that in any reasonable length of time. > >Now a number of 10 million decimals is approx. 33 million bits long i.e. >the Prime Exponent would be approx. 33 million. > >And I'm sure some of you have read the theories about the "missing >Mersenne", and the analysis done on the sequence of known Mersenne Primes. >If they turn out to be accurate, then we might be better looking at the 47 >- 49 million Prime Exponent range. Well, that might be a good idea, but don't higher exponents take longer to test in a manner that is slightly more than linear? > >For interest, has anyone calculated benchmarks, or run LL tests in those >ranges; I guess not many, 8 months is a long time to wait for a result !! Benchmarks have probably been done, but last time I checked, nobody had turned in a completed LL test. There are also no people doing only factoring assignments in that range, that I recall (getting the list that far down takes a LONG time on my dialup connection, and here at school I have fairly limited time online). This seems to make sense, since the factoring people are (presumably often) intersted in immediate gratification rather than boosting their producer standing. > >Dave > >"And the winning ticket in this year's Christmas Raffle is number >111.." I wonder whether any of the newspapers will publish the entire decimal text of the next prime It'd be funny to watch people open the newspaper on the bus and see that :-) Nathan __ Get Your Private, Free Email at http://www.hotmail.com _ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
RE: Mersenne: searching the biggies 2
>From: "Aaron Blosser" <[EMAIL PROTECTED]> >To: "Mersenne@Base. Com" <[EMAIL PROTECTED]> >Subject: RE: Mersenne: searching the biggies 2 >Date: Thu, 2 Mar 2000 21:33:23 -0700 > > >On the other hand, the existence of the EFF prize is a useful > >tool in convincing companies to run GIMPS, for most IT > >managers are quick to remind you that this *is* a business, > >and it is here to make money. (Then you hope that same > >IT manager hasnt the sophistication to calculate the actual > >odds of bagging the $100K, realizing that the mathematical > >expectation of the prize would not pay the extra electricity > >use...) > >Actually, the cost of electricity isn't a factor for most large companies. > >I can only rely on my knowledge of the various places I've worked. We all >know I worked at US WEST, and I can say that they leave their computers on >all the time. > >The other big telco I just spent the last 1.5 years at also leaves their >computers on 24x7, as does the company I work for now. > >The reasons for doing so are pretty simple: software deployment. > >When you want to push out a new version of Software Application version >x.xx, you do it at night when the employees won't be affected by a reboot. >So you tell people to leave their machines on, but just logout. > >Obviously, Wake-On-Lan is a great idea, but with legacy hardware, you >either >leave computers on all the time or you can't be as friendly with your >software deployment. > >That's why I hope that some brilliant person will be able to go to US WEST >and say "Hey, let's setup a Primenet Proxy, get these 30,000+ NT machines >looking for primes, and do some good research". That person won't be me, >by >the way. Or maybe someone can go to a company like MCI WorldCom and say >"Hey, let's get your 80,000+ NT machines looking for primes." Of course, I >wasn't about to make that suggestion myself...what can I say? I'm a little >skittish about such things. :-) > >Aaron Last time I checked, there were two universtites (labeled as such that is) at the top of the list but no companies really near the top. Nathan __ Get Your Private, Free Email at http://www.hotmail.com _ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
RE: Mersenne: Security and Prime95/mprime
> linux is a Good Move ... ceratinly, in its default state, it's at > least as secure (when used as a firewall) as anything emanating from > a certain purveyor of operating systems based near Seattle. It's > cheaper, too! Please note: Seattle is about 5000 miles from where I am, despite my address, and I'm about fifteen times closer to Brian than I am to Bill. I also make absolutely no comment (I'm explicitly not allowed to speak for anyone but myself in a personal capacity) about the relative suitability of linux and any other operating systems for hosting a firewall. I will make one snide comment though --- Drawbridge ran very successfully on that paragon of security MS-DOS before it was ported to FreeBSD, where it now runs equally successfully 8-) > Hey, I'm a security guru of a sort ... the idea is not to run > anything which gives crackers a toehold, or causes unacceptable > throttling of the firewall throughput. Indeed. My advice is never to run anything on a firewall which you can't prove to your complete satisfaction is absolutely necessary. Given that a FW can be run on almost any old kit, you can hardly complain about hardware costs. I used to run the aforementioned Drawbridge and MSDOS on a 386sx-16 with 4M RAM, a 40M disk and two cheap ISA 3Com cards. It was easily capable of supporting a 10M ethernet with a couple of dozen machines behind it. It may sound like paranoia --- it *is* paranoia --- but by being paranoid you have a hope of resisting attacks no-one has yet thought of. > Few of us know what code George has embedded in the code which > computes the tag which PrimeNet uses to check that incoming results > are genuine. However, this does not seem to present a major risk! George is an honorable man, I'm sure, and has not knowingly put in any loopholes. I'm equally sure that he's not infallible and that he will freely admit to this. Do *you* want to bet the security of your site even more than you are now doing? > I've run mprime on an anonymous FTP server for almost 18 months & > haven't had any incidents (yet). The basic rules are (a) always run Ditto with NTprime. It really does seem to be a well-behaved program. Even so, it doesn't run on my firewalls. > All this is virtually paranoia since I believe the risk posed by > running mprime is practically nil - but it's good practise, anyway. Yup. Paranoia is a survival characteristic. Paul _ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
Mersenne: Benchmarks
Hi all, Thanks to all that have submitted timings. There are still plenty of gaps to fill in and having multiple results for each machine is desirable. My first draft of the benchmark page is at http://www.mersenne.org/bench.htm Comments are of course welcome. Regards, George _ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
Re: Mersenne: searching the biggies
Hi, At 11:42 PM 3/2/00 -0500, Nathan Russell wrote: >>Nathan Russell asked: How much are the people who are trying to >>find a 10 million digit prime contributing to the search? I agree that all machines are contributing to our knowledge of Mersenne numbers. The gaps will eventually be closed. Since you're a relative newbie, the overriding goal of GIMPS has always been "have fun". That translates into doing the type of work that most interests you (as long as we all do the work in a coordinated manner). >That is precisely why I switched to GIMPS from another project whose sole >purpose was to simply recover a cute little, probably political, saying >that someone had hidden. There are those that view prime number hunting as equally useless. I don't view GIMPS as in competition with other distributed projects. The links at http://www.mersenne.org let you choose the project that is most appealing to you. All are worthy in their own way. >Two of their other projects lost GIMPS-years of work each because of >stupid bugs and I got fed up and left. Uh... we had a bug too. Ironically, it was announced on April Fools Day last year. That caused quite a stir. We lost roughly a GIMPS month of work. >This may seem like flamebait, and I do not intend it that way. Welcome aboard and good luck with your LL tests - but most importantly... Have fun, George _ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
RE: Mersenne: searching the biggies 2
> -Original Message- > From: Spike Jones [mailto:[EMAIL PROTECTED]] > > On the other hand, the existence of the EFF prize is a useful > tool in convincing companies to run GIMPS, for most IT > managers are quick to remind you that this *is* a business, > and it is here to make money. (Then you hope that same That may be true for some businesses, certainly not all. Encouragement that is, not _not _ making money! I've won money from computational number theory, most recently from the 512-bit RSA factorization. All of my winnings are immediately donated to charity. Colleagues in other companies have a similar policy. Paul _ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
Mersenne: Re: How much are the 10 M gamblers contributing?
Perhaps I'm a little under-speed here ... I understood that the $100,000 award was for the first 10 million digit (that is to say 10 million decimal digit Mersenne Prime). Now a number of 10 million decimals is approx. 33 million bits long i.e. the Prime Exponent would be approx. 33 million. And I'm sure some of you have read the theories about the "missing Mersenne", and the analysis done on the sequence of known Mersenne Primes. If they turn out to be accurate, then we might be better looking at the 47 - 49 million Prime Exponent range. For interest, has anyone calculated benchmarks, or run LL tests in those ranges; I guess not many, 8 months is a long time to wait for a result !! Dave "And the winning ticket in this year's Christmas Raffle is number 111.."
