Describe performance considerations

[divarvel]

In the whole authorization process, datalog evaluation is where your choices have a direct result in terms of performance.

We should describe the impact of datalog code design on evaluation performance.

So far, the things we have identified:

• the number of rules
• the use of regexes

The biscuit toolchain keeps track of the time spent evaluating datalog code, so we could also showcase how to use the tooling to measure performance characteristics of datalog evaluation