Add computing requirements

[MokhFn]

I am trying to launch the Index on 4 chains with data going back to 2018.
When doing so (on only one of the 4, in this case Cardano), the CLI crashes (killed) which was certainly caused by lack of resources.
It would be great to add performance benchmarks, or minimal computing requirements etc ...

If computing becomes such a huge component, maybe also use some computing engines (like Apache Spark) instead of pure python.
Spark is data centric, and can be very powerful when computing important volumes of data.

As a workaround, i had to add a 10Gb swapfile to handle the execution of only one chain.