Performance Tips

Avoid Scalar Indexing

Accessing elements of an NDArray one at a time (e.g., arr[5]) is slow and should be avoided. Indexing like this requires data to be trasfered between device and host and maybe even communicated across nodes. In the future, scalar indexing will emit a warning which can be opted out of. Several functions in the existing API invoke scalar indexing and are intended for testing (e.g., the == operator).

Kernel Fusion

cuPyNumeric does not fuse independent operations automatically. This is a priority for the beta release.