Add memrecap callback plugin

[sivel]

SUMMARY

Adds a memrecap callback plugin that utilizes the memory_profiler python module.

Example output:

MEMORY RECAP *********************************************************************************************************************************************************************************************************************************
Execution Maximum: 226.66MB

Gathering Facts: 225.33MB
Check who I am 1: 155.12MB
Check who I am 2: 142.66MB

ISSUE TYPE

• Feature Pull Request

COMPONENT NAME

lib/ansible/plugins/callback/memrecap.py

ANSIBLE VERSION

devel

ADDITIONAL INFORMATION

[sivel]

I'm now debating this callback. After some extensive testing, it seems that the way memory_profiler totals memory with children can report a value exceeding actual memory utilization.

The method it uses for calculating memory is to sum RSS from parent and children. However, due to COW and forks, it's likely that much of the memory reported via RSS is actually shared.

[sivel]

Closing in favor of #38675

#38675 is limited to where it can be utilized, but as described above, this PR will produce inaccurate results.