The P-1 factoring CUDA program

[LaurV]

Cudapm1 does not run on RTX2080Ti on Win7. All tests are ok, the "-selftest" passes (all 5 factors are found in seconds, the test is supposed to take 16 seconds, but it is much faster on this card), the -cufftbench (for both fft and threads) work well and write the correct files.

However, when "-selftest2" is run, or when a "real task" is done, the program stops with no GPU activity. For the -selftest2 the "stop" occurs when first GCD is called, and the CPU shows a 5% activity (one core of 20 is busy) but there is no progress and no output (the GCD in cause should take no more than 100 milliseconds, to half second). For a real "test case" the stop occurs exactly after the FFT, B1 and B2 are selected (and printed on screen), there is no CPU nor any GPU occupancy, but the GPU is "hooked" somehow because the clock (in GPU-Z) stays high, it does not go to 50MHz or so, as when the card is empty. In all these situations, the only possible exit is killing the process (ctrl+c will show the sigint message, but never exit).


Edit: this is valid for all versions I could dld from James' mirror (i.e. including the last ones). Anyone is running this in RTX cards?

[masser]

Did you try adjusting the UnusedMem setting in the .ini file? I only have a weak GPU, but I was having a lot of stalls until I turned up this value to about 20% of the GPU's memory.

[hansl]

Originally Posted by hansl

Would it be safe/reliable to create symlinks "libcufft.so.10.0" to the actual 10.1 file?

This was from a few months ago but I just got around to trying out and it definitely doesn't work to try symlinking/renaming 10.1 to 10.0.

I was able to build for 10.1 though, so its running now.

One question: It did some benchmarks where it looks like the best result was:

fft size = 5120K, ave time = 0.8334 msec, Norm1 threads 512, Norm2 threads 1024

However during the actual Pm1 I get:

Iteration 5000 M[redacted], 0x[redacted], n = 5120K, CUDAPm1 v0.22 err = 0.14844 (0:50 real, 10.1213 ms/iter, ETA 3:33:22)

I guess I was expecting the ms/iter to roughly match the msec from the benchmark, or does it not really work that way? Currently the difference is a factor of 12.14x

This is on a GTX 1660 6GB (non-Ti)

[kriesel]

Originally Posted by hansl

I guess I was expecting the ms/iter to roughly match the msec from the benchmark, or does it not really work that way? Currently the difference is a factor of 12.14x

The match is fairly close in CUDAPm1 v0.20, and not in v0.22.

With modern gpus it's hard to get a close match because clock speeds fluctuate, system activity varies, etc.

[c10ck3r]

Any guidance on how to correct error "device_number >= device_count" when using CUDAPm1 for the first time (0.22)?
TIA

[kriesel]

Originally Posted by c10ck3r

Any guidance on how to correct error "device_number >= device_count" when using CUDAPm1 for the first time (0.22)?
TIA

How many gpus are in the system? The first one is device number 0.
If that's not it, have a look further in the getting started guide

https://www.mersenneforum.org/showpo...51&postcount=4

[c10ck3r]

Originally Posted by kriesel

How many gpus are in the system? The first one is device number 0.
If that's not it, have a look further in the getting started guide

https://www.mersenneforum.org/showpo...51&postcount=4

Just 1, and device_number is set to 0. I downloaded all .dll files last week- perhaps one of them is causing the issue, since the error also shows '(This is probably a driver problem)'?
GTX1050 for reference, I have the following drivers all in the folder containing CUDAPm1:
cudart32_101
cudart64_31_9
cudart64_101
cufft64_10
cufft64_31_9
cufftw64_10

[hansl]

Originally Posted by c10ck3r

Just 1, and device_number is set to 0. I downloaded all .dll files last week- perhaps one of them is causing the issue, since the error also shows '(This is probably a driver problem)'?
GTX1050 for reference, I have the following drivers all in the folder containing CUDAPm1:
cudart32_101
cudart64_31_9
cudart64_101
cufft64_10
cufft64_31_9
cufftw64_10

Do you have the latest nvidia drivers installed? Nvidia control panel recognizes it, etc?

[kriesel]

Originally Posted by c10ck3r

Just 1, and device_number is set to 0. I downloaded all .dll files last week- perhaps one of them is causing the issue, since the error also shows '(This is probably a driver problem)'?
GTX1050 for reference, I have the following drivers all in the folder containing CUDAPm1:
cudart32_101
cudart64_31_9
cudart64_101
cufft64_10
cufft64_31_9
cufftw64_10

Which CUDA version CUDApm1 are you trying to run? On what OS, 32 or 64-bit? (Likely 64 if reasonably modern hardware). CUDApm1 needs a capable gpu, a suitable driver for the gpu, and cudart and cudafft dlls that match the CUDA version for which the CUDAPm1 executable was compiled and also the bitness.
You have the two extremes, very new and very old, plus a couple outliers cudart32_101 as 32-bit and cufftw which is not needed. CUDArt64_101 version does not match cufft64_10 (V10.1 vs. V10.0).

If you run nvidia-smi to get details about the gpu, what does it tell you? See https://www.mersenneforum.org/showpo...4&postcount=15
Have you run any other CUDA software on it? if so, what versions worked then?

A GTX1050 would need CUDA8 dlls to run mfaktc, but should run somewhat older CUDA level software such as CUDALucas or CUDAPM1 ok. I mostly run the later dates of CUDA5.5 or 5.0 CUDAPm1. Never 3.2 or older though. See https://download.mersenne.ca/CUDAPm1/old-experimental

[c10ck3r]

Originally Posted by kriesel

Which CUDA version CUDApm1 are you trying to run? On what OS, 32 or 64-bit? (Likely 64 if reasonably modern hardware). CUDApm1 needs a capable gpu, a suitable driver for the gpu, and cudart and cudafft dlls that match the CUDA version for which the CUDAPm1 executable was compiled and also the bitness.
[...]

A GTX1050 would need CUDA8 dlls to run mfaktc, but should run somewhat older CUDA level software such as CUDALucas or CUDAPM1 ok. I mostly run the later dates of CUDA5.5 or 5.0 CUDAPm1. Never 3.2 or older though. See https://download.mersenne.ca/CUDAPm1/old-experimental

Switching to 5.5 fixed it, thank you!

[kriesel]

Originally Posted by c10ck3r

Switching to 5.5 fixed it, thank you!

Sweet. You're welcome. What size exponents do you plan to run? See
https://www.mersenneforum.org/showth...365#post489365 and following posts for an idea of exponent limits on other gpu models.
Please provide any success or failure info versus exponent sizes tried, and I'll add it.
Also whether your GTX1050 a 2GB or 3GB unit.