Perf things that I know
As you will note while reading this, I haven't provided numbers to back up these statements. We'll get there eventually, so while I have experience with some of these, others are more "theoretical" based on my knowledge.
- the default of
gather_subset: [all]can consume a lot of RAM, and with a higher fork count causes CPU contention processing results in the main process. The CPU penalty is lessened with deepdish in 2.7
[min]is largely what people need and less impactful. This can be set via ansible.cfg as a default
- Not gathering facts when they aren't needed is a boost