Mersenne Digest Monday, June 14 1999 Volume 01 : Number 576
----------------------------------------------------------------------
Date: Sun, 13 Jun 1999 19:30:17 -0400
From: George Woltman <[EMAIL PROTECTED]>
Subject: Re: Mersenne: status of exponents
Hi all,
At 11:46 AM 6/13/99 -0500, several people wrote:
>The expiration policy is such-and-so...
Prime95 reports in with new expected completion dates as well as
next expected checkin date every N days where N is by default 28 days.
Your exponents are reassigned if you miss your next expected checkin date
by 60 days.
However, prime95 version 15 used a different algorithm. The program
reported an expected completion date when an exponent was reserved.
The exponent expired 60 days after the expected completion date is missed.
Exponents that are checked out by email do not follow a rigid
formula. Generally, progress must be reported every 4 or 5 months
and the range completed within a year. People I know such as Mr. Burge
and Mr. Sunde are given more slack than a name I do not recognize.
These exponents are usually recycled to people who cannot upgrade
from version 14 or are using Macs (which work a lot better on exponents
below 4.8M). Exponents above 5.2M are given to Primenet.
The "problem" exponents that started this thread almost assuredly came
from version 15 clients using the old expiration policy.
>Is "poaching" OK?
No. There's nothing I can do about it, but I certainly do not encourage it.
For the past two years it seems there has always been two or three people
testing the lowest available exponents. I don't think they have improved
their chances at all as they often report double-checks rather than first-time
checks.
>Oh great, I reported a result and got "exponent already tested" error.
Remember, you will get this error message when you retest an exponent
that was originally tested by buggy version 17. It is very likely that
you just completed the first CORRECT LL test.
That said, accidents happen. A manual tester can enter the wrong range,
an expired exponent can all of a sudden have its result reported, etc.
The system will never be perfect, but fortunately works as expected 99%
of the time.
>You should email the original person that reserved the exponent.
Well, my policy is not to give out email addresses.
>I'm not upgrading because I think my old P-whatever should run
>first time checks.
GIMPS does not mandate your computer do certain work. You can override
the defult behavior in the Test/Primenet dialog box. Remember, you are
here to have fun and if you don't mind waiting 6 months for an LL test,
that's fine by me. Your checkin every 28 days will let the server know
you are busy working on your exponent. (However, be reasonable. As this
thread shows if you grab an exponent that will take 4 years to test, you
can expect a "poacher" to finish it before you do. I would think one
year completion time would be OK though).
>Why do we care that these smaller exponents get tested in a timely manner?
The obvious answer is we want to make a relatively orderly determination
on the primality of every Mersenne number.
There is no sure-fire formula for detecting exponents that are no longer
being worked on. Once in a great while, I analyze the database and find
exponents that have "slipped through the cracks" or I think have been
abandoned and release them for reassignment. I do *not* email the affected
persons (I used to, but it was *way* too much work).
The good news is that the current prime95 expiration policy seems to
work very well. Thus, this problem should occur much less frequently
in the future.
Have fun,
George
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Date: Sun, 13 Jun 1999 21:00:48 -0400
From: "Rick Pali" <[EMAIL PROTECTED]>
Subject: Mersenne: Double-checking credits on Primenet?
I just started my second machine on double-checking and am curious on
whether I would expect to see my LL P90 year total increase when a
double-checking assignment is turned in.
Also, I notice that one can disable "Request whatever type of work makes
the most sense" and then proceed to select *two* types of work that you
want. How does the server decide which to send? I assume that it'll choose
factoring over double-checking, double-checking over primality testing,
and factoring over primality testing. Is this correct? If so, the windows
versions might better be served wait radio-buttons so that only one can be
selected.
Rick.
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Date: Sun, 13 Jun 1999 18:54:43 -0700 (PDT)
From: Ashton Vaz <[EMAIL PROTECTED]>
Subject: Mersenne: Re: Mersenne Digest V1 #575
Hi Aaron,
>Or this one:
>4465127 60 472.3 311.8 371.8 26-Feb-98 09:23 koma
>magek072
>
>Checked out 2/26/98, *NEVER* checked in at all, over a YEAR until it
>will
>expire.
>
>There are quite a few like that, so I'm gonna play God and take care of
>'em.
>:-)
>
>Here's one I just *love*:
>
>4787599 61 376.0 662.0 722.0 02-Jun-98 16:42
>andres
>
>We could wait around 2 years to finally get around to testing this
>obviously
>abandoned one, or I'll just do it now.
How about another option Aaron? You touch anyone's
exponents...especially mine and I report you to the FBI for stealing?
DAMNIT....I sure as hell hope the above message was in jest. You
better not play around with my exponents (or anyone else's for that
matter) or I'll raise hell on this list.
<And now back to George's regular GIMPS programming on my only
computer, my beloved P100!>
Later all.
Ashton
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Date: Sun, 13 Jun 1999 22:27:27 -0400
From: "Rick Pali" <[EMAIL PROTECTED]>
Subject: Mersenne: That's right agent, he stole my *number!*
From: Ashton Vaz
> How about another option Aaron? You touch anyone's
> exponents...especially mine and I report you to the FBI
> for stealing?
If you do take that action, I'd very much enjoy hearing their reaction.
:-)
Rick.
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Date: 13 Jun 99 21:11:07 MDT
From: Paul Derbyshire <[EMAIL PROTECTED]>
Subject: Mersenne: Re: TeX
Pierre Wargnier <[EMAIL PROTECTED]> wrote:
> I found them, the ones I have are in French unfortunately, but as there
> are 80 times more English than French on the net, the tutorials should
> be somewhere. Look in Yahoo, both TeX and LaTeX.
OK.
> There is a page at http://www.giss.nasa.gov/latex/index.html
Thanks.
> But it is a list of commands and not an introduction, perhaps there are
> links to introduction from here. In fact for basic documents you have a
> header of 5 line and all the remains are \chapter \section \subsection
> In Fact, you write a ASCII text that is similar to a normal TXT file. In
> these text you put commands like table/images inclusions/titles/cross
> references/bibliography... (need a bit reading before having all
> that :) )
Sounds ok so far...
> After that you need a special program that is TeX. TeX is like a
> compiler.
> You send your dumb Text file and you get a DVI file, a binary that can
> be sent to special printers. In fact as many peoples have not this you
> transform is into a Postcript file (ps, a bit like PDF§). This Postcript
> file can be previewed and printed with Ghost Script available for Win,
> UNIX and Mac perhaps.
Sounds steep to me...
> Most peoples write their text in one window, with the previewer in
> another. LaTeX is a set of macro commands to ease the use of TeX and
> should be used(I use latex and I don't know how hard pure TeX is). But
> the result is good, need a bit investment at the beginning(one day).
Hm.
> For the phony address, ask my admins, if there are not on the beach now.
What did they do, let their Internic bill get overdue? (The error after all
was unknown host!)
I suggest moving to a provider that is a tad more competent.
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Date: Sun, 13 Jun 1999 23:02:24 -0500
From: "Ralph Green, Jr." <[EMAIL PROTECTED]>
Subject: Re: Mersenne: status of exponents
Howdy,
I had 8 machines testing last year. Only one was internet connected. After
a couple of months of checking in results and getting no credit in the top
producer list, I got discouraged. It is not just that my producer stats did
not change. It implied to me that my efforts were wasted. I hope Aaron
does not make someone else feel that way. I have nearly finished a round
of upgrading most of these machines and I have not decided whether it is
"safe" to start testing numbers again.
Good day,
Ralph Green, Jr.
At 08:58 PM 6/13/99 +0100, Brian J. Beesley was seen to remark:
>Could I suggest that we do something to help those people with non-
>internet connected machines (or possibly machines which have to run
>LL testing clients which have no server support) to keep their
>progress up to date.
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Date: Sun, 13 Jun 1999 22:04:29 -0600
From: "Aaron Blosser" <[EMAIL PROTECTED]>
Subject: RE: Mersenne: status of exponents
> > WHAT DIFFERENCE WILL IT MAKE in
> > __your__ life when exponent so-and-so is completed ??
>
> When it comes right down to it, it will make *very* little difference to
> most of us when *any* exponent finishes. I guess that means we should all
> quit, eh?
Exactly. How we check numbers is nobody elses business. I don't like the
idea of unecessarily replicating work, but neither do I like the idea of
waiting 2 years to work on an exponent that's been abandoned.
> > This project was supposed to be fun. It is becoming intrusive.
>
> Interesting...I've never seen a less intrusive project in my life.
And I am having fun, especially the part where I learn about the inner
workings of our legal system! :-)
Seriously though, it's a hobby, we all have a different approach to it, but
if it weren't enjoyable in some weird way, I'd have quit on May 28, 1998.
Aaron
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Date: Sun, 13 Jun 1999 22:10:31 -0600
From: "Aaron Blosser" <[EMAIL PROTECTED]>
Subject: RE: Mersenne: status of exponents
> There is no sure-fire formula for detecting exponents that are no longer
> being worked on. Once in a great while, I analyze the database and find
> exponents that have "slipped through the cracks" or I think have been
> abandoned and release them for reassignment. I do *not* email
> the affected
> persons (I used to, but it was *way* too much work).
>
> The good news is that the current prime95 expiration policy seems to
> work very well. Thus, this problem should occur much less frequently
> in the future.
Agreed. I think it's important to note here that of the thousands of
exponents currently assigned for testing, I could find only a bit over a
dozen that were SOOO obviously abandoned (and so much time until they would
be reassigned) that I think the current system does in fact work quite
well...
Aaron
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Date: Sun, 13 Jun 1999 22:16:28 -0600
From: "Aaron Blosser" <[EMAIL PROTECTED]>
Subject: RE: Mersenne: Re: Mersenne Digest V1 #575
> >We could wait around 2 years to finally get around to testing this
> >obviously
> >abandoned one, or I'll just do it now.
>
> How about another option Aaron? You touch anyone's
> exponents...especially mine and I report you to the FBI for stealing?
> DAMNIT....I sure as hell hope the above message was in jest. You
> better not play around with my exponents (or anyone else's for that
> matter) or I'll raise hell on this list.
Wow! Well, I wasn't kidding, I did grab some exponents and am testing them.
I guess you'll have to call the FBI?
Obviously, opinions on this matter are VERY extreme!
As for you Ashton, which of those numbers in my message belonged to you?
Are you still testing it and, if so, why no updates in over a year?
Let me know and I'll leave you at it, but for goodness sake, if you have a
machine that slow, please consider factoring or double-checking smaller
exponents. It's just as important to do those tests and a slower machine is
much better suited. I don't use a hammer to cut wood, I don't use a
screwdriver to paint my walls, and I don't use a pocket calculator to do FFT
work, but for adding 2+2, it's just fine. Get the drift? Certain tools are
better suited to certain jobs. Find the job that your slower computer is
best suited for and go for it.
Am I just wrong in thinking this?
Aaron
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Date: Mon, 14 Jun 1999 07:06:53 +0200
From: Sturle Sunde <[EMAIL PROTECTED]>
Subject: Re: Mersenne: Re: Mersenne Digest V1 #575
> Am I just wrong in thinking this?
I fully agree with your opinions above[1], but you are wrong when you
make your own rules based on these opinions, and try to force other
people to follow your rules and not the commonly accepted ones. I don't
want to play with people who don't follow the rules or change the rules
during the game, and I don't have to.
This is supposed to be fun, and your behaviour makes it the oposite. I
don't want to stand guard over my exponents, sending in false progress
reports to make you stay away from them.
Follow the rules Aaron, or leave the game. Please.
__________________________
[1] Have a look at "Fact.P90 CPU yrs" on the top 100 list at Primenet,
where I'm S00113. My factoring to LL ratio is second on the list,
after "dodrillm". (Only a fraction of my work pass trough Primenet.)
- --
Sturle URL: http://www.stud.ifi.uio.no/~sturles/ Er det m}ndag i dag?
~~~~~~ MMF: http://www.alladvantage.com/go.asp?refid=BUP399 - St. URLe
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Date: Sun, 13 Jun 1999 23:26:56 -0600
From: "Aaron Blosser" <[EMAIL PROTECTED]>
Subject: RE: Mersenne: Re: Mersenne Digest V1 #575
> This is supposed to be fun, and your behaviour makes it the oposite. I
> don't want to stand guard over my exponents, sending in false progress
> reports to make you stay away from them.
Hey, whoa. I'm not asking anyone to send in false status reports. I *real*
status report every now and then would do. In fact, a status report at
least every 6 months seems quite prudent, don't you think?
And personally, I think that if a test will take over a year to complete,
you're probably better off doing factoring tests or double-checks, or maybe
some other (integer based) distributed computing project altogether. I like
GIMPS personally, but I'm not about to run Prime95 on my 486-75 laptop
except maybe for factoring assignments.
I know that factoring means you won't find the next record breaking prime,
but so what? I try to run factoring assignments on my computers on the
"recommended" 10:1 ratio... 1 factoring assignment for every 10 LL tests.
Factoring is every bit as important to GIMPS as anything else. We're now
doing first time LL tests in the 7M range...I can recall not too long ago
when I would get factoring assignments in that same range, and I like
knowing that I could use some of my slower machines to "pave the way" as it
were.
I'm not out to do all this just to get in the top-100 list...you could take
away all my accumulated CPU time (though the others in my team madpoo might
not like that) and that'd be fine because I'd still know that I'm
contributing.
Some people post to this list being upset that the work they turned in
hasn't shown up in the primenet status lists yet. I know that this is a
valid motivation for some people, but I do think they're missing a bigger
picture. We have thousands of people all tied together into one huge, very
well organized system. Scott and George have done wonders with putting this
altogether. I merely suggest that we try to clean up some of the bits that
ultimately will fall through the cracks. As I said before...exponents like
the ones that were pointed out earlier are a very rare exception to the
rule...but those exceptions must be dealt with to keep the coherency of
GIMPS intact.
But hey, this is just my opinion. After I test this little teeny tiny group
of numbers, I won't poach anymore and you can all do whatever, but I still
think it's a good idea to "clean house" every now and then.
Aaron
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Date: Sun, 13 Jun 1999 23:35:15 -0600
From: "Aaron Blosser" <[EMAIL PROTECTED]>
Subject: RE: Mersenne: status of exponents
> I don't really understand the urgency to get these exponents
> finished, either.
> So what if it takes 2 years to finish that check? Is one year to
> long? Six
> months? Six weeks? Should we tell people with Pentium 100s that
> we don't
> want their help? Considering we have an unlimited supply of
> exponents to test
> (barring a unexpected revelation that there are a finite number
> of Mersenne
> primes), we are better off (in terms of total work done per day)
> with older
> machines in addition to your new PIII-550's than we would be without them.
In one year, we just might be able to do first time checks on every exponent
under the currently unknown M38. Wouldn't it be nice if we could verify
that it is indeed the 38th Mersenne Prime, and not just the 38th *known*
Mersenne Prime?
I *gaurantee* that if EVERY OTHER NUMBER except this little group of a dozen
or so were tested, and only these few held us back from verifying the order
of the list, there would be very strong argument to get them tested right
away. If anything else, I'm just guilty of jumping the gun by a few months,
but considering that some of these exponents have been checked out for a
year and still have a year to go, I find the arguments that "well, I only
connect once a year" to be a bit tenuous at the outset.
> To make a long story short, just *ask* people... Mr. Woltman has
> a policy of
> not releasing email addresses, which I respect; since there are
> only a dozen
> or so of these suspected of abandoning their exponents, I would imagine he
> wouldn't be too busy to send them a quick email for you and let
> you know what
> they have to say. It just seems rude not to ask if you have
> contact information
> available.
I think a BETTER policy would be to automatically identify exponents which
meet some unusual criteria and automatically send them emails, asking them
"are you still running the software, how far along is it, do you have the
latest version, etc" and if they don't respond, then BOOM, back into the
pool of available exponents it goes.
Criteria for such an emailer might include:
- - hasn't reported results since it was first checked out
- - expected completion date at least 1 year in the future
- - running time exceeds 1 year with no checkins
etc. If an exponent met 2 or more criteria, they get an auto-email.
I don't know how feasible this is, but I think it'd help weed out those rare
numbers that *have* been abandoned and which, unfortunately, had long
completion times to begin with.
For other abandoned numbers checked out with the latest versions, they'll
expire 60 days after the last checkin date was missed (if I understood
Scott's comments right), so the problem will eventually go away. And that's
why we might as well clean out the problem exponents now anyway since no
more new problem exponents are likely to show up with the current system.
Aaron
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Date: Mon, 14 Jun 1999 00:37:46 -0700
From: Kevin Sexton <[EMAIL PROTECTED]>
Subject: Re: Mersenne: status of exponents
You will notice that in an email from George he said he does occasionally go
through the database and release those exponents that don't look like they will
be done by his own criteria and that he discourages "poaching". I would think
that you would trust him, and just get new exponents automatically. This will
help keep both you and others from "wasting" cpu time, duplicating first time
checks. I really don't think that anything will really "fall through the
cracks".
There isn't really much point in arguing about this further, its discouraged,
but we can't do much about people who insist on doing it.
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Date: Mon, 14 Jun 1999 08:44:52 GMT
From: "Brian J Beesley" <[EMAIL PROTECTED]>
Subject: Mersenne: Windoze joke
Hey, guys, this is not strictly mersenne related, but I think we all
deserve a laugh.
Microsoft have just released a patch for all versions of Win 9x (_all_
versions of Win 95 _and_ Win 98) which (is claimed to) resolve a
problem with systems hanging after 49.7 days continuous
operation. Only took them four years to find out that this might be
an issue ;-)
The patch can be downloaded from
http://support.microsoft.com/download/support/msfiles/ -
Vtdapi95.exe
(The existence of the file is _not_ a joke!)
Regards
Brian Beesley
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Date: Mon, 14 Jun 1999 10:15:13 +0200
From: Jan Pieter Kunst <[EMAIL PROTECTED]>
Subject: Re: Mersenne: status of exponents
"Brian J. Beesley" <[EMAIL PROTECTED]> wrote:
>I'd like to suggest:
[...]
>(b) an extra form is added to the PrimeNet Manual Exponent page, so
>that progress reports can be supplied manually on behalf of clients
>which can't do it automatically. (Don't even need to give a
>completion date really - just to say "I'm still alive" & keep the
>exponent reserved for another "expiry period" - but should have an
>optional field for estimated completion date, if known)
This is a very good idea. I am runnnig MacGIMPS on my PowerMac G3/233 and
that particular LL client has no server support yet. I would find it rather
unpleasant if someone snatched the exponent that was assigned to me because
s/he assumed that it was abandoned. After all, the fun part of GIMPS (to
me) is the knowledge that "I am testing exponent x that has been assigned
to me and to noone else".
JP
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Date: Mon, 14 Jun 1999 11:03:40 +0300
From: "Markus Laire" <[EMAIL PROTECTED]>
Subject: Mersenne: These go to 11 (WAS: blahblah...)
> >or, more concisely, (1+1+1)^(1+1) + 1.
> >Can anyone represent that number in fewer than (1+1+1)! ones?
This all depends on what operators and notations are accepted and
without specifying that, the whole question is useless.
What about without any ones at all: (With C++ operators)
((0++)++)*(((((0++)++)++)++)++)
or without any numbers: (With normal algebra)
((a/a)+(a/a))*((a/a)+(a/a)+(a/a)+(a/a)+(a/a)), a [belongs to] N
- -- Markus Laire <[EMAIL PROTECTED]> ICQ# 11887013
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Date: Mon, 14 Jun 1999 04:34:37 -0400 (EDT)
From: lrwiman <[EMAIL PROTECTED]>
Subject: Re: Mersenne: Windoze joke
> The existence of this file is _not_ a joke.
(not a direct quote, force of habit, I deleted the message before I
could respond).
Yes, but it seems like a joke to us Linux users out there,
for whom 2-day patches are not uncommon...
- -Lucas Wiman
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Date: Mon, 14 Jun 1999 10:53:13 +0200 (MET DST)
From: [EMAIL PROTECTED]
Subject: Re: Mersenne: LL and factoring & quitting
lrwiman <[EMAIL PROTECTED]> wrote:
>
> It has been mentioned several times recently that factoring is all integer
> work, and LL testing is nearly all floating point.
>
> It is my understanding that on intel CPU's, these are done on separate parts of
> the CPU. Would it increase net performance to do factoring and LL assignments
> at the same time?
>
If we can execute the two codes together, the functional units
will be better utilized. But we will need the combined memory bandwidth
for both codes, and enough cache for both working sets.
On Pentiums, a bigger concern is the number of registers --
most floating point intensive algorithms need several integer registers
for loop counters and address computations, so the integer code will
lack these. The two algorithms must be designed so the
control (i.e., branch) logic is identical -- we don't
want the integer code to be calling a subroutine
which executes the Euclidean GCD algorithm and repeatedly tests whether
the latest remainder is zero, while the floating point code
loops over the FFT output to square each element, for example.
When the control logic is identical for two algorithms, and
the subscripting (i.e., memory access) patterns are similar,
it may be feasible to merge integer and floating point algorithms
for improved functional unit utilization. For example, Ernst Mayer
is writing code which will do an integer FFT and a floating point
FFT of the same length concurrently.
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Date: Mon, 14 Jun 1999 10:49:34 GMT
From: "Brian J Beesley" <[EMAIL PROTECTED]>
Subject: Re: Mersenne: LL and factoring & quitting
lrwiman <[EMAIL PROTECTED]> writes:
> It has been mentioned several times recently that factoring is all integer
> work, and LL testing is nearly all floating point.
>
> It is my understanding that on intel CPU's, these are done on separate parts of
> the CPU. Would it increase net performance to do factoring and LL assignments
> at the same time?
There is _some_ scope here, but I think we need to be _very_
careful. Actually, the Intel CPU is a bit of a nightmare from this
point of view.
a) The integer multiplier and the floating-point multiplier share
common circuitry, therefore a (I)MUL and a FMUL cannot execute
in parallel. Since division is (only very partially) pipelined & takes
"forever", we avoid using it where practical. Therefore, the time-
dominant code in (integer) factorization is actually multiplication.
b) Some CPU types - including the Intel P6 family, for which the
potential gain would be greatest - already use the FPU (at least to
some extent) to do factorization - because can be faster to use the
FPU to do integer multiplies than it is to do them in the integer
ALU, despite the conversions - doing this reduces the demand on
the (very limited number of) (named) integer registers, too.
c) If you add extra integer mode instructions into the opcode
stream, you'd have to be very careful that these do not cause
opcode fetch, decoder or data bottlenecks, even when they don't
depend on shared execution units. We really _don't_ want to slow
down the LL code _at all_!
Looking at George's macros yesterday, I was struck by how
efficient they are in terms of usage of FPU registers & L1 data
cache lines. Really you couldn't squeeze anything else in there,
unless it would run entirely in (integer) CPU registers, or you were
prepared to take the "hit" involved in L1 data cache line misses
quite frequently.
> Also, I'm going to quit first time LL testing. Call me impatient,
but I don't
> want to wait until early July for my exponent to finish, thus I'm going to
> switch to double-checking.
Hi, Mr. Impatient!
Seriously, though, I wonder how many others will do this now that
it looks like the chance of grabbing the $50K has gone?
Also, how much latent interest might there be in firing straight at
the $100K prize, even with run lengths > 1 year?
Regards
Brian Beesley
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Date: Mon, 14 Jun 1999 06:09:16 EDT
From: [EMAIL PROTECTED]
Subject: Re: Mersenne: Windoze joke
> Microsoft have just released a patch for all versions of Win 9x (_all_
> versions of Win 95 _and_ Win 98) which (is claimed to) resolve a
> problem with systems hanging after 49.7 days continuous
> operation. Only took them four years to find out that this might be
> an issue ;-)
The reason it took so long is that it wasn't until now that ANYONE
had Win9x run that long without rebooting. They might find the
same sort of bug in Linux in, oh, about 10 years.
Randy Given
[EMAIL PROTECTED]
http://members.aol.com/GivenRandy
public key at http://members.aol.com/GivenRandy/pgpkey.asc
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Date: Mon, 14 Jun 1999 06:41:51 -0400 (EDT)
From: lrwiman <[EMAIL PROTECTED]>
Subject: Re: Mersenne: LL and factoring & quitting
all,
Thanks to Brian J Beesley, and Peter Lawrence for the info on why my whole
2 simultanious tests idea wouldn't work.
Just an idea that ran through my sleep deprived brain...
>> Also, I'm going to quit first time LL testing. Call me impatient,
>> but I don't
>> want to wait until early July for my exponent to finish, thus I'm going to
>> switch to double-checking.
> Hi, Mr. Impatient!
;-)
> Seriously, though, I wonder how many others will do this now that
> it looks like the chance of grabbing the $50K has gone?
Well this isn't why I'm stopping first time LL tests, but I imagine that
many people will be quitting GIMPS altogether because of the loss of prize
money, unless of course...
> Also, how much latent interest might there be in firing straight at
> the $100K prize, even with run lengths > 1 year?
Well, I'll bet if we ask Scott and George real nice, maybe they will add
specific facilities for checking in this range (in V19?). We can call it
the "win $100,000 range," or something equally corny...
We will of course have to check factors considerably further than we are doing
on our current exponent range (due to the increased LL iteration time.) I
think that someone (Brian...?) did test for all 10,000,000 digit primes
<36,000,000 for factors <2^40. Maybe George can add these to his database, or
something. This range looks promising since the Island theory says the M43
should be around 35462263 (I rounded up to the next prime).
As for the > 1 year runtime, I think the recent "Poaching" thread has shown
that many people are willing to wait more than one year for an LL test to
complete, especially (I imagine) when they get the gleam of capitalistic
ferver in their eyes for erm... scientific discovery.
In any case, the EFF's prize money can only give us exposure, and new members.
After all, the reason for the donated CPU cycles is completly imaterial.
Speaking of the EFF, was the lucky 38th (known) assigned after the EFF
anounced its prize money? If so, did the EFF speed us on our way to victory?
Regards,
- -Lucas Wiman
P.S. - I sent out my various files pertaining to my 45% completed exponent,
so please don't send me any more requests for those files...
P.P.S. - 5:36AM, well, I guess that's what I get for reading 3 year old
mersenne mailing list archives. Fasinating reading, that (seriously).
P.P.P.S. - Don't you just love P.P.P.S.'s
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Date: Mon, 14 Jun 1999 07:14:45 -0400 (EDT)
From: lrwiman <[EMAIL PROTECTED]>
Subject: Re: Mersenne: Windoze joke
>> Microsoft have just released a patch for all versions of Win 9x (_all_
>> versions of Win 95 _and_ Win 98) which (is claimed to) resolve a
>> problem with systems hanging after 49.7 days continuous
>> operation. Only took them four years to find out that this might be
>> an issue ;-)
> The reason it took so long is that it wasn't until now that ANYONE
> had Win9x run that long without rebooting. They might find the
> same sort of bug in Linux in, oh, about 10 years.
Win9x is not run in, for example, serving an ISP, where Uptime is 6 months or
more, like Linux is. Such a bug would probably be caught, in about 49.7 days.
With a patch in a couple of weeks at the outside. Also, Win95 (in my
experience) locks up so frequently, and requires reboots so often, that you
would be lucky to keep it up 49.7 days, and even then, who is to say which
bug caused the reboot.
Farting in Win95's general direction, :-)
- -Lucas Wiman
P.S. If these views offended you, I remind you of two rights: The right to
ignore me completly, and the right to use a technologically inferior operating
system if you so desire
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Date: Mon, 14 Jun 1999 12:30:51 +0100 (BST)
From: Chris Jefferson <[EMAIL PROTECTED]>
Subject: Mersenne: Factoring
I was just wondering, could anyone give me any info on how factoring is
done, is there a preliminary factoring before numbers send out, how high
we factor, what possible factors are, etc. and also, I would really like
to see the maths behind it as well. I need something to study over summmer
vac :)
- ------------------------------------
Chris Jefferson, Girton College, Cambridge, [EMAIL PROTECTED]
- ------------------------------------
Someone may have beaten me to Fermat's Last Theorem, but I've done
Riemann's general equation. However it won't fit in my signature file...
- ------------------------------------
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Date: Mon, 14 Jun 1999 14:01:24 +0200
From: "Steinar H. Gunderson" <[EMAIL PROTECTED]>
Subject: Mersenne: Re: Mersenne Digest V1 #575
On Sun, Jun 13, 1999 at 04:35:36PM -0700, Mersenne Digest wrote:
>Should do, however sometimes (for a reason I don't know) it's
>anything up to a day old.
I didn't find myself there at all (neither full name, nor username). And
I started this before PrimeNet became standard.
>Actually it's irrelevant what speed your processor is working at so
>far as credit is concerned. George Woltman (the author of the
>software) benchmarks the program using a "standard" system, which
>happens to be a P90 he has lying around somewhere (was probably state-
>of-the-art when he got it).
I've talked to him lately. The P90 is upgraded now, and Prime95 v19 will
provide a benchmark based on something newer (like his PII-400). It is
already reporting 0.3secs/iter on my PC, where it should be 0.2...
(Thankfully, the `moving average' function saves the estimates.)
>Conversely AMD
>K6 chips aren't as good as you'd expect (no pipelining in the FPU at
>all), and Cyrix chips are plain miserable.
K6s and Cyrixes are relatively good at integer maths -- let them factor
with the integer algorithm, would by my suggestion.
- ---snip---
>on the C400 making the speed comparison every more impossible:)
For benchmarks, turn to the benchmark pages on the GIMPS homepages :-)
- ---snip---
>> This is a fun project
>It is also to be useful.
I think George's original idea of it was fun.
- ---snip---
>btw, I disagree with the current policy of not letting slowish machines like
>this do LL tests, this machine cranks out a exponent every 60 days, has been
>an old faithful, I see no reason to retire it from the test, hence have not
>updated it to the current software, its still running 16.x.
You can choose exactly what assignments you want, even with 18.x. There are
checkboxes to override the automatic selection.
- ---snip---
>I thought that if no check-in was done in 60 days, the number was put back in
>the pool.
No, if no check-in has been done in 60 days _after the exponent was expected
to complete_, it is put back into the pool. Of course, once in a while,
the software will report `new expected completion dates' to the server, and
this date will be moved.
- ---snip---
>The owner is "dsh21". Mail him and ask why.
[...]
>The owner is "koma". Mail him and ask why.
[...]
>Why don't you mail "andres" and ask if it is abandoned first?
I have to agree on this policy. One mail, give them a week or so to reply,
and if they don't, take the exponent. (Didn't IPS have an automatic system
at one point? If you look in the readme file, it said it didn't work at
expected, so they took it out.)
- ---snip---
>This is an excellent point, I think we ought to take notice. It's
>certainly p*ss*d me off a bit with the Proth project to find that,
>out of 4 primes I've discovered, 2 are "rediscoveries" of numbers
>that other people have been working on without reserving ranges via
>the perfectly satisfactory facilities provided.
We should certainly prevent things like this from happening to GIMPS...
For now, we can rely on the users, I hope. Suggested policy: One mail,
one week.
- ---snip---
>Some people that are out of contact may be using the buggy version 17, and
>their work is wasted.
Probably not -- if they _have_ an Internet connection and have downloaded
v17 with it, they will probably also have received the v17 bug warning, and
they will probably at least make their computers report in now and then...
- ---snip---
>Also, I'm going to quit first time LL testing. Call me impatient, but I don't
>want to wait until early July for my exponent to finish, thus I'm going to
>switch to double-checking.
Now, isn't it great that v17/v18 actually _has_ something to do for impatient
users, namely double-checking? Remember, everybody: Nobody forces you to do
double-checking. It's _your_ option.
/* Steinar */
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End of Mersenne Digest V1 #576
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