[GRASS-dev] --with-opencl without a GPU

[Yann Chemin]

> I hope so, for Linux Ivy Bridge chips that's all you'd be able to get,
> but running multi-core GPCPU is still a time win. I'm not sure if OpenCL
> lets you do GPU+CPU or you have to choose one or the other, or if it
> can do both at the same time if the CPU memory array size gets limited
> by the GPU memory limit.

When coding it, you can specify the type of host (GPU, CPU, FPGA, etc)
or you can set up a small code assessing what is up and running at the
moment (say 2 GPUs, 2 CPU), in that case you can set the code to use
the resources devices (here there are 4 devices available). You can
partition your code in sections and let those sections run on
different devices as found in the initial test. You can also partition
your data the same way throughout the available devices.

Short answer: Yes can use GPU+CPU, but you have to think about it and
code it specifically