ECM for CUDA GPUs in latest GMP-ECM ?

[RichD]

I am now trying to build GMP-ECM w/ CUDA on my Linux box. A few hundred curves a day in not cutting it for me anymore.

I tried configure with -—enable-gpu and it doesn’t find cuda.h. I then added -—with-cuda=/usr/local/cuda-8.0.

Not sure why I needed to do that because other packages (mfaktc, mmff, msieve) all build/make fine as is.

BTW, I’ve added the following to .bashrc per nvidia documentation.

export PATH=/usr/local/cuda-8.0/bin:$PATH
export LD_LIBRARY_PATH=/usr/local/cuda-8.0/lib64:$LD_LIBRARY_PATH

The output is the following, so I am lost.

configure: Using cuda.h from /usr/local/cuda-8.0/include
checking cuda.h usability... no
checking cuda.h presence... yes
configure: WARNING: cuda.h: present but cannot be compiled
configure: WARNING: cuda.h:     check for missing prerequisite headers?
configure: WARNING: cuda.h: see the Autoconf documentation
configure: WARNING: cuda.h:     section "Present But Cannot Be Compiled"
configure: WARNING: cuda.h: proceeding with the compiler's result
configure: WARNING:     ## ------------------------------------------------ ##
configure: WARNING:     ## Report this to ecm-discuss@lists.gforge.inria.fr ##
configure: WARNING:     ## ------------------------------------------------ ##
checking for cuda.h... no
configure: error: required header file missing

I searched lists.gforge.inria.fr but couldn’t find anything meaningful.
I don't recall seeing a pre-built Linux x86_64 for CUDA 8.0 fly by.

Originally Posted by RichD

I searched lists.gforge.inria.fr but couldn’t find anything meaningful.
I don't recall seeing a pre-built Linux x86_64 for CUDA 8.0 fly by.

This is something I used that worked before. Perhaps it may help...or not.

[jw@localhost ~]$ export PATH=/usr/local/cuda-7.0/bin:$PATH
[jw@localhost ~]$ export LD_LIBRARY_PATH=/usr/local/cuda-7.0/lib64:$LD_LIBRARY_PATH
[jw@localhost trgpu]$ su
Password:
[root@localhost trgpu]# ldconfig /usr/local/cuda-7.0/lib64
[root@localhost trgpu]# make check

## GPU program works only when in root mode.

[chris2be8]

I had a lot of fun getting it to work. See http://mersenneforum.org/showthread....mfs#post364978 and nearby posts for details of what I had to do.

Chris

[RichD]

I don’t have a problem with CUDA or my GPU setup. I am running two GPU cards in a box with nvidia toolkit, samples, SDK and drivers all working properly. I have been running mfaktc for months using CUDA 8.0. At times I will stop one of the mfaktc jobs and run mmff for a while. I even run msieve poly selection using the GPU with no problems building or making.

I can’t get past the configure step in ECM-GMP let along even trying to make it. I do have a successful make without the GPU.

I don’t want to go back to CUDA 7.0 or 7.5 because they both had the carry bit bug in them. I’ll just wait until the next release of configure (ECM-GMP) for CUDA 8.0 to see if that will address my problem.

[0PolarBearsHere]

Originally Posted by wombatman

I truthfully don't remember all the steps I went through to get everything compiled successfully with VS2012 (I have no experience with VS2015). I'm attaching the gpu_ecm exe I have built. Try it out and see what dlls you need for it.

Are you able to compile a cuda8 version?

[wombatman]

Not a clue, but I can give it a shot. What compute capability do you want/need?

[0PolarBearsHere]

I've got a gtx1080 that I want to test with ecm to see how it compares with trial factoring.

[VBCurtis]

I can't think of any candidate numbers that fit within the GPU-ECM 1018-bit limit but would otherwise be trial-factored rather than sieved. What numbers are you interested in testing?

[xilman]

Originally Posted by 0PolarBearsHere

I've got a gtx1080 that I want to test with ecm to see how it compares with trial factoring.

I can provide a bunch of GCW numbers if you are interested.

[0PolarBearsHere]

Originally Posted by xilman

I can provide a bunch of GCW numbers if you are interested.

Definitely interested. I'll need some instructions about how to test them though.

[pepi37]

Originally Posted by VBCurtis

I can't think of any candidate numbers that fit within the GPU-ECM 1018-bit limit but would otherwise be trial-factored rather than sieved. What numbers are you interested in testing?

So GPU has limit, when you use ECM, and what is about -pm1?
In that case is same limit ?

Last two weeks I play with ECM-GMP ( ver 7.0.4) for Windows. When I do Pminus1 in Prime95 I learn ( what i need to learn) in one day, and found many factors.
But learning curve of ECM_GMP is such a different thing. It is so erratic

For example

C:\Users\Alpha-I7\Desktop\New folder\ecm>ecm -mpzmod -one -v -nobase2 50 < test.txt
GMP-ECM 7.0.4-dev [configured with GMP 6.1.1] [ECM]
Running on Alpha-I7-PC
Input number is 4*53^500288+1 (862636 digits)
Using REDC
Using B1=50, B2=1356, polynomial x^1, sigma=0:10519400687847901454
dF=12, k=2, d=90, d2=7, i0=-6
Expected number of curves to find a factor of n digits:
35 40 45 50 55 60 65 70 75 80
Inf Inf Inf Inf Inf Inf Inf Inf Inf Inf
Step 1 took 58407ms
********** Factor found in step 1: 123685

Since I use -one in command line ECM-GMP , when is found factor should skip for next one, but no: he stop ( I terminate it after 15 minutes)
And settings B1 and B2 are so much different then setting same values in Prime95.

I would like to "master" ECM-GMP for at least same speed and same numbers of factors found like in Prime95, but it looks like it will be hard task to do it.