CUDA - Class problems. Factor divisible by 2, 3, 5, 7, or 11

[ET_]

Originally Posted by TheJudger

It doesn't mean that this is a (big) issue, just want to know if this happens for you, too. And would be good to know if this occurs in earlier builts (or versions) aswell.

Speaking for mfaktc in debug mode (compiletime option) there are lots of checks on (interim) results. Sometimes the results are not within the expected range but this is OK because the issue was already on the input, e.g. the kernel is designed to handle factors abot 2⁶⁴ and on input are numbers slightly below 2⁶⁴. Mfaktc checks the input before writing (error-)messages (ignoring issues when input was not within the designed limits). This could be the case here, too.

Oliver

In your opinion, and since we are testing very high values, do you think a version 0.29 could be necessary or the issue is definitely too small and too insignificant to consider a software revamping?

[newalex]

I have the same problem as Dylan. I have a system with Windows 7 x64 and GeForce 1080. CUDA 10 is installed here. After compilation from sources I get "Class problems. Factor divisible by 2, 3, 5, 7, or 11" error on any worktodo.txt when try to run mmff.

[Dylan14]

Sorry if this is considered a necropost, but since Jerry (flashjh) has been contacted recently for CUDAlucas (per this post by Serge) and he built the previous builds of mmff for Windows, perhaps we should contact him to see if he can get mmff to compile correctly for higher CUDA levels (so that me and newalex can use it)?

[ET_]

Originally Posted by Dylan14

Sorry if this is considered a necropost, but since Jerry (flashjh) has been contacted recently for CUDAlucas (per this post by Serge) and he built the previous builds of mmff for Windows, perhaps we should contact him to see if he can get mmff to compile correctly for higher CUDA levels (so that me and newalex can use it)?

Any news about it?

[Dylan14]

Originally Posted by ET_

Any news about it?

I have not heard back from Jerry yet. In fact, he has not been on here since June 2.

[Fan Ming]

I succeed at compiling mmff with CUDAv10.1 toolkit and Microsoft Visual Studio 2012 on Windows 10 without class problems. Thanks for clues provided by nomead! Attached file contains Makefile.win I used and the compiled Windows executable.
I tried a few test cases:

MMFactor=31,64,65
MMFactor=61,549e9,550e9
MMFactor=31,56e9,57e9
MMFactor=31,54e9,55e9
MMFactor=31,414.5e11,415e11
MMFactor=31,414e11,415e11
MMFactor=31,416e11,417e11

Here are results:

no factor for MM31 in k range: 4294967298 to 8589934595 (65-bit factors) [mmff 0.28 mfaktc_barrett89_M31gs]
no factor for MM61 in k range: 549000000000 to 549755813887 (101-bit factors) [mmff 0.28 mfaktc_barrett108_M61gs]
no factor for MM61 in k range: 549755813888 to 550000000000 (102-bit factors) [mmff 0.28 mfaktc_barrett108_M61gs]
MM31 has a factor: 242557615644693265201 [TF:67:68:mmff 0.28 mfaktc_barrett89_M31gs]
found 1 factor for MM31 in k range: 56G to 57G (68-bit factors) [mmff 0.28 mfaktc_barrett89_M31gs]
no factor for MM31 in k range: 54G to 55G (68-bit factors) [mmff 0.28 mfaktc_barrett89_M31gs]
no factor for MM31 in k range: 41450G to 41500G (78-bit factors) [mmff 0.28 mfaktc_barrett89_M31gs]
MM31 has a factor: 178021379228511215367151 [TF:77:78:mmff 0.28 mfaktc_barrett89_M31gs]
found 1 factor for MM31 in k range: 41400G to 41500G (78-bit factors) [mmff 0.28 mfaktc_barrett89_M31gs]
no factor for MM31 in k range: 41600G to 41700G (78-bit factors) [mmff 0.28 mfaktc_barrett89_M31gs]

It seems the these results are quite correct - no missed factors nor false positives. However, I don't know the mechanism of mmff and don't know how to do further tests. (Can anyone help this? Thanks!) I didn't test fermat numbers, either.

[yorix]

Originally Posted by Fan Ming

I succeed at compiling mmff with CUDAv10.1 toolkit and Microsoft Visual Studio 2012 on Windows 10 without class problems. Thanks for clues provided by nomead! Attached file contains Makefile.win I used and the compiled Windows executable.

Well done! Thanks a lot =)

This mmff was tested for my GTX 1650 without problems.
No missed factors:

// Mersenne tests with known factors

MM31 has a factor: 242557615644693265201 [TF:67:68:mmff 0.28 mfaktc_barrett89_M31gs]
found 1 factor for MM31 in k range: 56G to 57G (68-bit factors) [mmff 0.28 mfaktc_barrett89_M31gs]
MM31 has a factor: 178021379228511215367151 [TF:77:78:mmff 0.28 mfaktc_barrett89_M31gs]
found 1 factor for MM31 in k range: 41400G to 41500G (78-bit factors) [mmff 0.28 mfaktc_barrett89_M31gs]

// Fermat tests with known factors

F118 has a factor: 2030912570882086247957711831528946513898296129355777 [TF:170:171:mmff 0.28 mfaktc_barrett172_F96_127gs]
found 1 factor for k*2^120+1 in k range: 1527T to 1528T (171-bit factors) [mmff 0.28 mfaktc_barrett172_F96_127gs]
F132 has a factor: 46842071212744845599962218807393559947324348854918184961 [TF:184:185:mmff 0.28 mfaktc_barrett185_F128_159gs]
found 1 factor for k*2^135+1 in k range: 1075T to 1076T (185-bit factors) [mmff 0.28 mfaktc_barrett185_F128_159gs]

F28 has a factor: 1766730974551267606529 [TF:70:71:mmff 0.28 mfaktc_barrett89_F32_63gs]
found 1 factor for k*2^36+1 in k range: 25709M to 25710M (71-bit factors) [mmff 0.28 mfaktc_barrett89_F32_63gs]
F31 has a factor: 46931635677864055013377 [TF:75:76:mmff 0.28 mfaktc_barrett89_F32_63gs]
found 1 factor for k*2^33+1 in k range: 5460G to 5470G (76-bit factors) [mmff 0.28 mfaktc_barrett89_F32_63gs]
F37 has a factor: 701179711390136401921 [TF:69:70:mmff 0.28 mfaktc_barrett89_F32_63gs]
found 1 factor for k*2^39+1 in k range: 1073741824 to 2147483647 (70-bit factors) [mmff 0.28 mfaktc_barrett89_F32_63gs]
F42 has a factor: 3916660235220715932328394753 [TF:91:92:mmff 0.28 mfaktc_barrett96_F32_63gs]
found 1 factor for k*2^45+1 in k range: 111310G to 111320G (92-bit factors) [mmff 0.28 mfaktc_barrett96_F32_63gs]
F43 has a factor: 7482850493766970889994241 [TF:82:83:mmff 0.28 mfaktc_barrett89_F32_63gs]
found 1 factor for k*2^45+1 in k range: 212G to 213G (83-bit factors) [mmff 0.28 mfaktc_barrett89_F32_63gs]
F48 has a factor: 2408911986953445595315961857 [TF:90:91:mmff 0.28 mfaktc_barrett96_F32_63gs]
found 1 factor for k*2^50+1 in k range: 2139G to 2140G (91-bit factors) [mmff 0.28 mfaktc_barrett96_F32_63gs]
F52 has a factor: 389591181597081096683521 [TF:78:79:mmff 0.28 mfaktc_barrett89_F32_63gs]
found 1 factor for k*2^54+1 in k range: 16777216 to 33554431 (79-bit factors) [mmff 0.28 mfaktc_barrett89_F32_63gs]
F52 has a factor: 1475547810493913550438096961537 [TF:100:101:mmff 0.28 mfaktc_barrett108_F32_63gs]
found 1 factor for k*2^54+1 in k range: 81900G to 81911G (101-bit factors) [mmff 0.28 mfaktc_barrett108_F32_63gs]
F72 has a factor: 1443765874709062348345951911937 [TF:100:101:mmff 0.28 mfaktc_barrett108_F64_95gs]
found 1 factor for k*2^74+1 in k range: 67108864 to 134217727 (101-bit factors) [mmff 0.28 mfaktc_barrett108_F64_95gs]
F77 has a factor: 3590715923977960355577974656860161 [TF:111:112:mmff 0.28 mfaktc_barrett120_F64_95gs]
found 1 factor for k*2^79+1 in k range: 5G to 6G (112-bit factors) [mmff 0.28 mfaktc_barrett120_F64_95gs]
F83 has a factor: 246947940268608417020015902258307792897 [TF:127:128:mmff 0.28 mfaktc_barrett128_F64_95gs]
found 1 factor for k*2^87+1 in k range: 1595G to 1596G (128-bit factors) [mmff 0.28 mfaktc_barrett128_F64_95gs]
F86 has a factor: 6195449970597928748332522715641578258433 [TF:132:133:mmff 0.28 mfaktc_barrett140_F64_95gs]
found 1 factor for k*2^88+1 in k range: 20018G to 20019G (133-bit factors) [mmff 0.28 mfaktc_barrett140_F64_95gs]
F88 has a factor: 148481934042154969241780501829489000449 [TF:126:127:mmff 0.28 mfaktc_barrett128_F64_95gs]
found 1 factor for k*2^90+1 in k range: 119G to 120G (127-bit factors) [mmff 0.28 mfaktc_barrett128_F64_95gs]
F90 has a factor: 985016348367230226078056532654006730753 [TF:129:130:mmff 0.28 mfaktc_barrett140_F64_95gs]
found 1 factor for k*2^92+1 in k range: 198G to 199G (130-bit factors) [mmff 0.28 mfaktc_barrett140_F64_95gs]
F94 has a factor: 76459067246115642538831634131564386844673 [TF:135:136:mmff 0.28 mfaktc_barrett140_F96_127gs]
found 1 factor for k*2^97+1 in k range: 482G to 483G (136-bit factors) [mmff 0.28 mfaktc_barrett140_F96_127gs]
F96 has a factor: 8453027931784477309850388309101819121893377 [TF:142:143:mmff 0.28 mfaktc_barrett152_F96_127gs]
found 1 factor for k*2^101+1 in k range: 3334G to 3335G (143-bit factors) [mmff 0.28 mfaktc_barrett152_F96_127gs]
F107 has a factor: 3346902437331832346018436558958369334886401 [TF:141:142:mmff 0.28 mfaktc_barrett152_F96_127gs]
found 1 factor for k*2^111+1 in k range: 1073741824 to 2147483647 (142-bit factors) [mmff 0.28 mfaktc_barrett152_F96_127gs]
F116 has a factor: 4563438810603420826872624280490561141381005313 [TF:151:152:mmff 0.28 mfaktc_barrett152_F96_127gs]
found 1 factor for k*2^120+1 in k range: 3G to 4G (152-bit factors) [mmff 0.28 mfaktc_barrett152_F96_127gs]
F133 has a factor: 3836232386548105510567872577199319351015739156856833 [TF:171:172:mmff 0.28 mfaktc_barrett172_F128_159gs]
found 1 factor for k*2^135+1 in k range: 88000M to 88100M (172-bit factors) [mmff 0.28 mfaktc_barrett172_F128_159gs]
F146 has a factor: 13235038053749721162769301995307025251972223086886913 [TF:173:174:mmff 0.28 mfaktc_barrett183_F128_159gs]
found 1 factor for k*2^148+1 in k range: 33554432 to 67108863 (174-bit factors) [mmff 0.28 mfaktc_barrett183_F128_159gs]
F147 has a factor: 88894220732640180500173831441107513117330143465963521 [TF:175:176:mmff 0.28 mfaktc_barrett183_F128_159gs]
found 1 factor for k*2^149+1 in k range: 67108864 to 134217727 (176-bit factors) [mmff 0.28 mfaktc_barrett183_F128_159gs]
F164 has a factor: 343390041044181900054983258125842173093877961821829176754177 [TF:197:198:mmff 0.28 mfaktc_barrett204_F160_191gs]
found 1 factor for k*2^167+1 in k range: 1835M to 1836M (198-bit factors) [mmff 0.28 mfaktc_barrett204_F160_191gs]
F166 has a factor: 8005705634611551271269985633916919970948098093294822472135213057 [TF:212:213:mmff 0.28 mfaktc_barrett215_F160_191gs]
found 1 factor for k*2^171+1 in k range: 2674670M to 2674671M (213-bit factors) [mmff 0.28 mfaktc_barrett215_F160_191gs]
F172 has a factor: 492544145925433733451855533863925475950550777193174123310743553 [TF:208:209:mmff 0.28 mfaktc_barrett215_F160_191gs]
found 1 factor for k*2^174+1 in k range: 20569M to 20570M (209-bit factors) [mmff 0.28 mfaktc_barrett215_F160_191gs]
F178 has a factor: 479744144560996421795040836675707785358665797968769873751310337 [TF:208:209:mmff 0.28 mfaktc_barrett215_F160_191gs]
found 1 factor for k*2^180+1 in k range: 313M to 314M (209-bit factors) [mmff 0.28 mfaktc_barrett215_F160_191gs]
F184 has a factor: 22953190542224652377639611826608942557783370967811443134226759681 [TF:213:214:mmff 0.28 mfaktc_barrett215_F160_191gs]
found 1 factor for k*2^187+1 in k range: 117M to 118M (214-bit factors) [mmff 0.28 mfaktc_barrett215_F160_191gs]

[storm5510]

I have the same issue with my GTX 1080. kriesel indicated I needed a CUDA 8 build to run on Windows 10 v1903 x64. The installed driver set is CUDA 10.x. None of the ones posted will run, or so it seems.

I saw a recommendation to use CUDALucas to perform a memory test on my GPU. I did. There were no errors.

[kriesel]

Originally Posted by storm5510

I have the same issue with my GTX 1080. kriesel indicated I needed a CUDA 8 build to run on Windows 10 v1903 x64. The installed driver set is CUDA 10.x. None of the ones posted will run, or so it seems.

I saw a recommendation to use CUDALucas to perform a memory test on my GPU. I did. There were no errors.

How big a memory area did you test? I had a gpu that tested fine with the default 10 blocks of 25MB, but failed a lot in the middle third of its ram. That was an old GTX480.

-memtest s i           s = # of chunks of memory
                       i = number of iterations

                       tests s 25MB chunks of memory doing i repetitions of
                       a 100,000 iteration loop on each of 5 different LL
                       test related sets of data. Each iteration consists
                       of copying a 25MB chunk of data, then re-reading
                       and comparing that copy to the original.

A GTX1080 is 8GB. Test as big a memory area as it will let you run. On my GTX1080 and Win7 that is 317 blocks. One pass takes about 2 hours.

CUDALucas -memtest 317 1

[storm5510]

Originally Posted by kriesel

A GTX1080 is 8GB. Test as big a memory area as it will let you run. On my GTX1080 and Win7 that is 317 blocks. One pass takes about 2 hours.

CUDALucas -memtest 317 1

I ran the below. It took about 95 minutes.

CUDALucas -memtest 256 1

I remember seeing "256" in the .ini file. I did a quick check. 265 is the limit on Windows 10, in my case. Anything beyond,"Out of memory." If there had been a larger gap, I would re-run the test. With a difference of 9, I really do not see the need.

[kriesel]

Originally Posted by storm5510

I ran the below. It took about 95 minutes.

I remember seeing "256" in the .ini file. I did a quick check. 265 is the limit on Windows 10, in my case. Anything beyond,"Out of memory." If there had been a larger gap, I would re-run the test. With a difference of 9, I really do not see the need.

256 x 25 = 6400MB. You're skipping testing on more than 20% of the gpu's 8192 MB ram. Just FYI.
To test the full ram, don't have anything else running on the gpu at the time. If it's the display gpu too, that might be a factor. Use nvidia-smi.exe to see what's running on the gpu and using its ram.