[PyCUDA] pyCUDA and streams

[Magnus Paulsson]

> If by 'working' you mean 'actually overlapping', here's an additional
> subtlety. If 'exec' includes any kind of memory allocations, those are
> implicitly synchronization points--so you might be synchronizing without
> even seeing it. A memory pool would be a good solution for that (but
> would only help on the second run through).
>

pyFFT (and my toy code) only allocate memory at the start. Otherwise
we would not see overlap in the "Working.py".

> If however 'not working' means 'wrong results', then something's even
> more fishy.
>
> Andreas

By working I mean overlapping exec and mem-copy.

-Magnus