Newer milestone thread

[bcp19]

Originally Posted by rcv

My biggest concern was that long-time, dedicated, trustworthy PrimeNet users no longer have an equal chance to obtain some of the best assignments. (I hope I'm included in that set or users. My first LL, in 1997, was a little over 2,000,000.) No matter how much GPU272 team members can contribute to LL/DC, you are only a drop in the bucket compared to the traditional Prime95/PrimeNet users.

Now, can we sanely discuss the merits and the alternatives and the pros and cons? Can we attempt to reach some consensus and/or compromise? [Before we engage in wide-spread implementation of a policy that might be detrimental to the overall well-being of GIMPS.]

Well, how about this:

Just because an exponent is 'the lowest unverified' so far, does that statistically make it more likely to be a prime? Why is it considered a 'plum'? What makes IT more likely to be THE ONE? And now the biggest one: To whatever answer you give to the above questions, Can you PROVE it?

Face it, your arguements truly are baseless, since the next prime could be the one you are already working on, or it may not happen until the wave gets to 86M or higher. Just because GPU72 happens to get ahold of a low number means absolutely nothing, except to people who want to bleat about unfairness and those who want to say "All Mp below XXX have been checked once".

[chalsall]

Originally Posted by Dubslow

To play the devil's advocate , neither of these two posts is really responding to the criticism he presents.

Grasshopper...

What you have not yet learnt is you do not always have to answer all questions directly. Particularly when the questions are not asked honestly.

Watch and learn.... ()

[Dubslow]

Originally Posted by chalsall

Grasshopper...

What you have not yet learnt is you do not always have to answer all questions directly. Particularly when the questions are not asked honestly.

Watch and learn.... ()

...Please explain what makes you think they aren't honest.

I do agree that we are abusing GPUto73, however as I said, it's out of a lack of alternatives and nothing more. (If PrimeNet were fully functional and optimal, then as D points out all too often, GPUto73 would never have been necessary.)

[chalsall]

Originally Posted by Dubslow

...Please explain what makes you think they aren't honest.

When someone asks questions but doesn't answer them.

[c10ck3r]

I like bacon.

-This post accomplishes more than the past few. It informs the reader of an unknown fact that cannot be disproved. Now, for the love of [Deity], please stop using the Mile/millstone thread to bicker back and forth. It causes my heart to pound approx. 5 beats per minute faster when I see a "new" milestone, just to be disappointed when there isn't one.
/rant

[Prime95]

Originally Posted by rcv

I believe GPU272'ers are hard-working, dedicated, technically advanced users who want what's best for GIMPS. But you GPU272'ers just can't take criticism.

This should be amended to some or many can't take criticism. Many see a critical rcv post and have a knee-jerk reaction to bash back.

For those that do not know, rcv has contributed more to GIMPS than most. He does not toot his own horn, but his initial efforts at GPU sieving code is the basis for the code I'm now working on incorporating into mfaktc. I probably learned more about good CUDA programming techniques from his program and documentation than I've learned from reading Nvidia manuals.

So, before launching a knee-jerk counter-attack ask yourself have I contributed that much to GIMPS?

It's really George's decision, as he is the one to make announcements, and it's his credibility on the line. [I suspect there's a little cross-checking that goes on behind the scenes just prior to an announcement that M(x) is the nth Mersenne Prime.] And the language that is used in the announcement can vary with the circumstances. "All candidates below x have been independently verified by at least two independent users at least two years apart" versus "All candidates below x have been tested twice" versus "At least two reports have been received for all candidates below x".

Sorry to disappoint. There is no behind-the-scenes cross-checking. Brian Beesley used to do triple-checking if the 2 LL tests were done by the same user. However, he stopped at somewhere below M2000000.

When the milestones page says "GIMPS proves Mxxxxxxxx is the x-th Mersenne Prime", there really should be a giant asterisk next to "proves". With a community-based project it is impossible, or nearly-impossible, to eliminate the possibility of a malicious user submitting bogus double-checks just for the fun of it.

The core question is does GPU72/73 increase those risks. I personally don't think so. The dedicated users of GPU72/73 are the least likely to engage in malicious activities. Furthermore, if GPU72/73 did not exist, could we remove the giant asterisk? Nope.

I think the true independent proof of "Mx is n-th Mersenne prime" is many years down-the-road when computers are so fast that somebody decides to test all the exponents below x and compares them to our database.

My biggest concern was that long-time, dedicated, trustworthy PrimeNet users no longer have an equal chance to obtain some of the best assignments.

This is undeniably true, but I think in somewhat different way. The number of users that knew exactly when the plum assignments were made available and were willing to make the effort to get them was very, very small. (I was one. Once a month or two I'd open prime95 at the appointed hour and unreserve big exponents to get the plum smaller assignments). These few users are likely dedicated enough to learn of GPU72/73 and get their plum assignments that way.

Where GPU72 hurts is the average user no longer has even a small chance of getting a plum assignment (if prime95 happened to contact the server within a few hours of the golden hour) they now have virtually no chance as the bot got them all within minutes. Most users probably don't care, but some might resent being reduced to "second-class" GIMPSers.

I had hoped that once GPU72 "caught up" with its TF efforts, it would end up keeping a small number of the plum assignments (say a 100 or so) to satisfy GPU72ers day-to-day needs. To the average PrimeNet user there is little difference between the old system and a system where GPU72 has pre-reserved the lowest 100.

I'm not sure how GPU72 is currently configured. Do they keep the 100 smallest? or is it a 1000? or would it be fairer if it made half of the smallest exponents available to average PrimeNet users by say only holding exponents that are 1 mod 4? This is a fair topic for debate.

On the plus side for the average user, the GPU72 project -- necessitated because PrimeNet doesn't handle GPU clients -- now gets exponents that are factored 4 bits deeper or approximately a 4% better chance of resulting in a new prime.

[Batalov]

I am amazed how high-volume this thread became.

To me, this is all a storm in a teacup. You know why? Because >99% of the GIMPS contributors are not reading this thread. They don't have a brain. They only have a CPU. They are unsupervised computers. They are objective, they are not picky - they take any assignment the server sends them and do it. Sometimes they take a summer vacation - the class is out, the lab/class computers are down for three months; no big deal. Yeah, they return non-matching results sometimes; but they don't obsessively try to be right, they get another assignment. The caravan goes on no matter what! But as Dennis Miller used to close his rants - "...of course, that's just my opinion. I could be wrong."

[Prime95]

Originally Posted by Batalov

To me, this is all a storm in a teacup. You know why? Because >99% of the GIMPS contributors are not reading this thread. They don't have a brain. They only have a CPU. ... that's just my opinion. I could be wrong."

You are of course right. But still it is our duty to treat them as fairly as possible.

[chalsall]

Originally Posted by Prime95

I'm not sure how GPU72 is currently configured. Do they keep the 100 smallest? or is it a 1000? or would it be fairer if it made half of the smallest exponents available to average PrimeNet users by say only holding exponents that are 1 mod 4? This is a fair topic for debate.

I have always tried to be as open and clear as I could be about what GPU72 was doing.

The Available LL/DC Assignments report clearly shows that there are currently 75 low LL candidates available, and 200 low DCs.

I'm more than happy to adjust things such that these numbers are lower, and/or we leave a certain percentage available directly through Primenet.

[axn]

Originally Posted by Prime95

have I contributed that much to GIMPS?

Nothing much. With that, I'll shut up.

[LaurV]

Originally Posted by Prime95

Sorry to disappoint. There is no behind-the-scenes cross-checking. Brian Beesley used to do triple-checking if the 2 LL tests were done by the same user. However, he stopped at somewhere below M2000000.

I am available anytime to triple check suspect exponents, if they come to me by themselves (i.e. I have no time to crawl PrimeNet DB and no expert knowledge in how to do it well) and by an official way (this means mainly George, but can also be Chris, few others, and not any anonymous guy sending me exponents to triple check). So, George, if you have a list of such suspect exponents, send it to me. I will - very fast - triple check as much as I can from it, and send you the logs eventually (last iterations) so you can check if the TC was really done. You should also mention if the test can be done by CL (no shifts, but I can vary FFT lengths just to increase a bit the safety) or it need a P95 run. Newer expos (which had a CL done already) will be in this situation, but also older, small expos (because older versions of P95 may not have the shifting implemented for LL, only for DC). Running small expos on P95 won't be a problem. For expos larger then 30M I would prefer CL run. As I said, I have the hardware.

I understand if no credit can be given for this activity.

(did not read the rest of the posts in the thread, still reading into it, brb)