After getting the graph divided and labeled, I went back to improve speed. Using a separate setup function to draw the divisions and labels that also allocated all memory block, I was able to redraw data on the graph at very high speeds.
I find these numbers impressive for a script-based language. One million data points in 23 ms is fast enough to do real-time data—if you can get a million points of data that fast. Hundred million data points sets are a bit absurd in a browser just because of the memory required, but are possible.