20200409, 21:30  #2058 
P90 years forever!
Aug 2002
Yeehaw, FL
7,541 Posts 

20200409, 21:50  #2059  
"Mihai Preda"
Apr 2015
3×457 Posts 
Quote:


20200409, 21:53  #2060  
∂^{2}ω=0
Sep 2002
República de California
19·613 Posts 
Mihai in #2049:
Quote:
I have a special interest here  once I finish my current round of v20related updates to Mlucas I intend to get up to speed on the programming model used for gpuowl, with a longterm goal of enhancing it to support the negacyclic DWT (on top of the Mersennestyle IBDWT) and rightangletransform data layout needed to support Fermatmod arithmetic. For my Fermat number testing to date I've used pairs of sidebyside runs, both with 0 shift but at different FFT lengths. The problem is, as we approach F33, the window of possible sizes for the smaller, slightlylessthanpowerof2 FFT length of said run pairings rapidly shrinks. For F31 a smallerFFT length of 120M = 15*8M is gonna really be pushing the accuracy limits of a doublesbased FFT. For F33 we'd need at a minimum 496M = 31*16M, but that prime 31 means a 31DFT, and even the bestofbreed such algorithm is horribly inefficient. So I originally had in mind some highlycomposite length < 512M, specifically 504M = 63*8M, but even though 63 = 3^2.7 is decently smooth, the result will likely be slower than the accompanying 512M run. But in the meantime I've worked out all the needed details to do residueshifted Fermatmod arithmetic  it's quite a bit more involved than Mersennemod, for reasons I'll detail soon in an upcoming post to the "Pepin tests of Fermat numbers beyond F24" thread  but now that I've worked out the mathematical details and have working proofofprinciple code, it's clear that performancewise it should be no worse than Mersennemod with shift. So F33  starting with a deep p1 stage 1 (where it's crucial to obtain a correct residue, since absent a resulting factor one wants to distribute said residue to many stage2 subintervalrunners) can use paired runs at 512M FFT, each with a different shift. Last fiddled with by ewmayer on 20200409 at 21:55 

20200409, 22:37  #2061  
"Mihai Preda"
Apr 2015
2533_{8} Posts 
Quote:


20200410, 16:28  #2062 
"Mr. Meeseeks"
Jan 2012
California, USA
2^{3}·271 Posts 
Tried to submit an LL result, got "Did not understand 1 lines."
{"exponent":"54907981", "worktype":"LL", "status":"C", "program":{"name":"gpuowl", "version":"v6.11252gaf403e2"}, "timestamp":"20200410 14:05:02 UTC", "user":"kracker", "computer":"core", "aid":"xxxxxxxxxx", "fftlength":3145728, "res64":"xxxxxxxxxxxxx", "offset":0} 
20200410, 16:59  #2063 
"TF79LL86GIMPS96gpu17"
Mar 2017
US midwest
3×1,811 Posts 
gpuowlv6.11255g81fa7c3 for Win 7 x64 or up
Latest commit build, build log, help output, etc.

20200410, 19:27  #2064  
∂^{2}ω=0
Sep 2002
República de California
19×613 Posts 
Quote:
One could object "but they accept GIMPS newprime announcements, based on matching independent floatingFFT runs"  true, and that establishes the minimum baseline for e.g. an F33 testing effort. Further, my ongoing Fermat number tests  currently finishing up run #2 of F30 @64M FFT, first run @60M finished late last year  all deposit interim every10Miter checkpoint files, so knowing the format of same, anyone could do a parallel (in the sense of multiple runs, each covering a separate 10Miter subinterval) triplecheck using whatever code they like. For F33 the resulting fileset, at ~1 GB per checkpoint and 858 such, will occupy slightly less than 1TB, so any such file sharing might have to be done using physical disk drives, depending on the state of storage technology at that timepoint. Last fiddled with by ewmayer on 20200410 at 19:29 

20200410, 19:43  #2065  
Einyen
Dec 2003
Denmark
3158_{10} Posts 
Quote:


20200410, 22:02  #2066  
"James Heinrich"
May 2004
exNorthern Ontario
23×149 Posts 
Quote:
I'm just waiting to hear back from Mihai regarding the change in format, I'll post back when the manual form will accept these results. 

20200411, 00:36  #2067  
"Mihai Preda"
Apr 2015
3×457 Posts 
Quote:


20200411, 00:45  #2068 
"TF79LL86GIMPS96gpu17"
Mar 2017
US midwest
3×1,811 Posts 
Very different; V0.6 was before the switch to JSON.
https://www.mersenneforum.org/showpo...9&postcount=28 
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