The previous section raises the question of how to handle a higher number of concurrent requests, as depicted in the following diagram:

A server under an increasing load

The previous section explained how to avoid wasting resources to leverage the computing power of your server. But actually, there is no magic; if you want to compute even more things per unit of time, you need more computing power, as depicted in the following diagram:

Scaling using more powerful hardware

One solution could be to have a more powerful server. But you could be smarter than that and avoid buying expensive hardware by studying the shape of the workload and make appropriate decisions at the software-level.

Indeed, there are chances that your workload varies a lot over time, with peaks and holes of activity. This information suggests that if you wanted to buy more powerful hardware, its performance characteristics would be drawn by your highest activity peak, even if it occurs very occasionally...