Plotting millions of points can be slow. Real slow... 😴
So why not use density maps? ⚡
The mpl-scatter-density mini-package provides functionality to make it easy to make your own scatter density maps, both for interactive and non-interactive use. Fast. The following animation shows real-time interactive use with 10 million points, but interactive performance is still good even with 100 million points (and more if you have enough RAM).
Extension for matplotlib to rapidly graph lots of points
Found via this neat article about bnechmarking memory allocations; the author replays all allocations from a few minutes of playing Doom 3, and graphs the time they took.