Node 10.10.0 is not caching env variables (slow "getenv")

[KindWizzard]

Version: 10.10.0
Platform: Darwin 17.7.0 xnu-4570.71.2~1
Docker: node:10-slim

In the environment in which we run Node.js, is about 5,000 env variables. With such a large value of variables, it takes much longer to read them. The problem is that Node.js does not cache the result of getenv method call. As a result, the performance of the application falls critically.

That's how the bottom of the flame graph looks like:

Half of the execution time is spent reading env-variables.

[AyushG3112]

Can't you implement caching on your end?

[richardlau]

See #3104 for previous discussion.