Hi guys,
I've been assisting in quality assurance testing of Prime95 for some
time and have had one of my systems run halfway through a LL test on
a 10 million digit number. Unfortunately the intermediate result I
have does not match the only other available value, which means that
one of us is wrong.
The problem could be a program bug (unlikely), an undiscovered bug in
either Athlon or Pentium III floating-point arithmetic (again
unlikely) or a random hardware glitch in either my system or the
system against which I'm checking (much the most likely).
To eliminate the first two possibilities it is neccessary to re-run
the first half of the test. As I have savefiles at 1 million
iteration intervals this could be done in parallel by 17 systems; I
will be running (at least) one of these myself but would like to
recruit 16 volunteers to check the remaining intervals.
Volunteers should be running Prime95 or mprime v20.6 on an Intel
Pentium II or PIII system. Please do not volunteer if you intend to
run on an Athlon since this would make it impossible to determine if
a processor bug is to blame. You will need to upload the save file, a
binary file approximately 5 megabytes in size, from my ftp site, and
unzip it; your segment of the work will take 13 CPU days (on a
PII-400, according to George Woltman's benchmarks) with checkpoints
at 1.3 day intervals. You should be prepared to check each checkpoint
and report to me immediately should you find a discrepancy. I would
like to finish the work as soon as reasonably possible, so reasonably
fast systems are indicated - at least PII-400 running continuously.
Unfortunately I cannot offer any recognition other than my personal
thanks. (i.e. no CPU time credit, sorry!)
If you're interested, please reply to me and I'll supply further
instructions (how to download your specific file, precise details of
how to set up the run and a list of my intermediate residuals at your
checkpoints to compare with your values).
Regards
Brian Beesley
_________________________________________________________________________
Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm
Mersenne Prime FAQ -- http://www.exu.ilstu.edu/mersenne/faq-mers.txt
