I see your point, but that's a somewhat contrived example: If you display per-minute data for an entire month you won't have the horizontal resolution (43200 to

I see your point, but that's a somewhat contrived example: If you display per-minute data for an entire month you won't have the horizontal resolution (43200 to 44640 data points) to plot them all! If you want zoomable charts to allow for increasing resolution, then the chart lib should ask the controller for a specific resolution and range on demand. Even then, 500KB of numeric JSON data compresses really well (I tested with 1 month of real-world per-minute data: 92KB).