Flaky Test test_operator:test_custom_op_fork hanging

[rondogency]

Description

test_operator.py - test_custom_op_fork

Python custom operator test hanging causing some CI to timeout

Occurrences

http://jenkins.mxnet-ci.amazon-ml.com/blue/organizations/jenkins/mxnet-validation%2Funix-cpu/detail/PR-17270/16/pipeline/298

http://jenkins.mxnet-ci.amazon-ml.com/blue/organizations/jenkins/mxnet-validation%2Funix-cpu/detail/PR-17241/19/pipeline/294

Note that the above PR are C++ custom operator and has no connection with Python custom op

What have you tried to solve it?

1. Tried "python tools/flakiness_checker.py test_operator.test_custom_op_fork -n 100" on a EC2 and the test will intermittently hang

2. It may be related to the deadlock issue fixed last year mx.nd.Custom not working in subprocess #14396

[anirudh2290]

@rondogency I was also able to reproduce the hang. Can you disable the test, to unblock CI for now.

[rondogency]

@anirudh2290 PR is here #17481

[samskalicky]

@Zha0q1 FYI