[Starpu-devel] StarPU task_submit failure on gpu

[Ankit Khandelwal <amkhande@umail.iu.edu>]

Hello Team,

I am working with StarPU and trying to submit task on GPU's. While making StarPU the configuration instruction showed that there were 4 GPU    devices available. I believe if the device is available it would by default enable its support for CUDA during installation. 
Next, what I did was: changed .where variable in codelet structure cl of vector_scal.c in basic_example directory of StarPU to following:
.where = STARPU_CUDA
STARPU_USE_CUDA macro works as expected and detects CUDA. 
The compilation of program is successful but when I try to run it it gives me below error:
[starpu] Unexpected value: <-19> returned for starpu_task_submit
I did try to explicitly state the STARPU_NCUDA=2. On adding this it showed up below message:
[starpu][_starpu_init_machine_config] Warning: 2 CUDA devices requested. Only 0 available.
what does only 0 available mean? Also, I did run normal basic cuda programs and they were working fine.
Can you please help me with understanding of this behavior?

Regards,
Ankit Khandelwal