Opencensus-core memory leak

[danwbyrne]

Please answer these questions before submitting a bug report.

Opencensus Version

v0.0.16

Node Version

v11.13.0

What did you do?

Here is a minimal repo which outlines the issue: https://github.com/danwbyrne/opencensus-leak

What did you expect to see?

All tests pass without triggering the memory leak warning.

What did you see instead?

tests trigger the memory leak warning.

Additional context

We recently switched from custom monitoring with opentracing to use opencensus at https://github.com/neo-one-suite/neo-one going forward, however this memory issue is coming up in CI / locally causing our ~2000 test suite to OOM. Any help would be appreciated :)

[mayurkale22]

@danwbyrne Thanks for reporting this! Your PR would be much welcome :)