2014-09-11, 14:52 | #1 |
"Patrik Johansson"
Aug 2002
Uppsala, Sweden
2^{3}·53 Posts |
CUDALucas not redoing iterations with larger FFT
I just had the following problem with CUDALucas v2.04 Beta:
Code:
Iteration 24020000 M( 36163033 )C, 0x47f4b44347a56afb, n = 1920K, CUDALucas v2.04 Beta err = 0.2812 (1:07 real, 6.7233 ms/iter, ETA 22:40:21) Iteration 24030000 M( 36163033 )C, 0x5f9ad444634e1734, n = 1920K, CUDALucas v2.04 Beta err = 0.2734 (1:08 real, 6.7129 ms/iter, ETA 22:37:07) Iteration = 24037901 >= 1000 && err = 0.35938 >= 0.35, fft length = 1920K, not writing checkpoint file (because -t is disabled) and exiting. Is there a way I can manually set it to use a larger FFT to get past this point? (I know this is not the lastest version of CUDALucas, but if I run a later version I use on another computer I just get: ./CUDALucas-2.05-Beta-r64-Linux-x86-64: error while loading shared libraries: libcufft.so.5.5: cannot open shared object file: No such file or directory ) |
2014-09-11, 20:00 | #2 |
"Patrik Johansson"
Aug 2002
Uppsala, Sweden
2^{3}×53 Posts |
I managed to get past the point using the same fft size by changing 0.35 in the source to 0.40, and recompiling the program. (I compiled it from source when I first started using this version.)
I used the new version only for 12651 iterations, then stopped it and switched back to the original version. In a day or so I will se if this double-check matches the original test. |
2014-09-12, 00:56 | #3 |
"Carl Darby"
Oct 2012
Spring Mountains, Nevada
315_{10} Posts |
If I remember correctly 2.04 can take a command line parameter eg, -f=4000k to use a particular size fft. On the other hand, I don't see any reason that what you have done will give an incorrect result.
Last fiddled with by owftheevil on 2014-09-12 at 00:57 |
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