@leofang

@dalcinl I had a tiny bit of time over the holidays to pick up this old task that has been on my mind for a couple of years. I noticed DistArray is the workhorse behind mpi4py-fft, however it requires subclassing numpy.ndarray

which makes it not possible to use cupy.ndarray as a drop-in replacement, as CuPy currently does not support subclassing (cupy/cupy#3972).

Is it absolutely necessary to make DistArray a subclass? Can it be tweaked (hopefully mildly) to become an array container to support both NumPy and CuPy arrays (and potentially other array/tensor libraries)? Could this change break backward compatibility? From my first glimpse it seems possible but I'd like to discuss further and see if I miss anything.