Running `kill 0` in MacOS pipeline causes denial of service.

Have you tried trouble shooting?

Yes.

Agent Version and Platform

Version of your agent? 2.140.2

OS of the machine running the agent? OSX

VSTS Type and Version

VisualStudio.com

If VisualStudio.com, what is your account name? http://myrjola.visualstudio.com

What’s not working?

Relevant public pipeline: https://dev.azure.com/myrjola/pipelines-test/_build?definitionId=1

Given the following pipeline config:

pool:
  vmImage: 'macOS 10.13'

steps:
- script: kill 0

The build eventually fail with the following error:

Running the build repeatedly exhausts the agent pool:

Note that the public agent pool is 10 parallel jobs. There are less than ten parallel jobs running and still three jobs are blocked from starting. They show the following:

So jobs are not starting even though they should:

I tried running kill 0 to terminate the whole process group because I had tasks that kept on running forever possibly because they spawned background processes.

Agent and Worker’s Diagnostic Logs

I could not find the logs from the hosted agent and worker.

[TingluoHuang]

i am going to close this issue for now since it’s not really a problem for the agent itself. you might want to report at developer community if you have concern about the host pool availability.

[myrjola]

Thank you for the investigation! The host pool recovered during the night.