JIT: implement memory pystats collection

[diegorusso]

Feature or enhancement

Proposal:

In order to improve the JIT memory allocation, we need to know how much memory it uses.

Specifically it would be useful to know the following metrics:

• code total memory
• data total memory
• trampoline total memory
• padding total memory
• memory that we free

Use the pystats infrastructure to collect these stats.

Has this already been discussed elsewhere?

No response given

Links to previous discussion of this feature:

This feature has been discussed with @brandtbucher in the past months.