CULA R12 Matlab can't find cula link.dll

[stj8kk74ho]

Just downloaded and installed CULA Premium (no Basic installed before), including setting Paths. Copied the in the Blog linked matlab_cula.bin in the Matlab bin Folder and started Matlab with it.

So far all looks good.

But when trying to execute

tic; A = A*A'; toc;

an error Msg pops up: cula_link.dll The specific module could not be found (see attachement 1).

It seems that something with the Path Entries (see attachement 2) is wrong, could so far not figure out what.

System ist Win7 64 bit, Matlab 2009b 64bit, Graphics Card GTX480/Driver 275.33 and Tesla C250/Driver 275.65, CUDA 4.0.

Q: How to get it up and running?

[stj8kk74ho]

One Addition regarding the Error msg. Besides the posted PoPup ErrMsg in Matlab directly

libmwblas: load error: cula_link.dll
Caught std::exception Exception message is:
cula_link.dll

appears.

[kyle]

MATLAB isn't finding the CULA DLL; double check CULA_BIN_PATH_64 is under your main PATH environment variable as well.

As a test, in MATLAB, you can change directories to the CULA DLLs (i.e. 'cd C:/Program Files/CULA/R12/bin64/') and try your command there.

[stj8kk74ho]

Kris, thank you for your fast response.

After Staring Matlab with the downloaded matlab_cula.bat the current Folder in Mathlab is c:/windows/system32.

When changing the Directory in Matlab to

cd('C:\Program Files\CULA\R12\bin64')

and then doing the calculation there is no error an the timing is
tic;Fdax2 = Fdax * Fdax';toc
Elapsed time is 2.696249 seconds.

Compared to when starting matlab w/o CULA it is

tic;Fdax2 = Fdax * Fdax';toc
Elapsed time is 5.574355 seconds.

This means CULA seems basically to work.

As you can see from the attachement the Path should be set correctly.

Q: Why does matlab after startup still pointing to c:/windows/system32 as active directory and how to fix that it points automatically to C:\Program Files\CULA\R12\bin64 ?

Another Q regarding GPU usage. As my System has 2 CUDA-capable GPU'S (C2050 and GTX480) does CULA automatically select which of those it is using or uses it both GPU's?
How to see which GPU is or GPU's are currently by CULA used?

[kyle]

Great, that means that it's simply a configuration error.

You need to add CULA_BIN_PATH_64 to your 'Path' variable.

I've attached a crude capture to demonstrate this.

Capture.PNG (9.63 KiB) Viewed 32361 times

[stj8kk74ho]

kyle, many thanks. Done and its working now. CULA is great!

May i ask my second Q again:

As my System has 2 CUDA-capable GPU'S (C2050 and GTX480) does CULA automatically select which of those it is using or uses it both GPU's?
How to see which GPU is or GPU's are currently by CULA used?

[kyle]

For multi-GPU systems, CULA will default to the "best" GPU in the system. In your case, it should be choosing the C2050. You can run the device query program included as it will list the GPU in the order they are chosen.

[stj8kk74ho]

Looked for the device Query Program and could not find it. Where is it located?

[kyle]

Oh sorry, that's with the CUDA SDK.

The NVIDIA control panel -> Workstations should also list the GPUs in "ranked" order.

[stj8kk74ho]

You are right. Nvidia Control Panel lists the C2050 first.

Nvidia System Monitor allows to show and log GPU specific Parameters.

Thank you for your great support. Issue solved and Q answered.

[kyle]

Great! If you seeing good results in a real MATLAB application, please let us know!

[john]

Can't argue with 2x for just changing an environment variable!