🌱 addr.Suggest should lock a file instead of memory

[vincepri]

Envtest is often running in parallel when using go test, which spins up
multiple indipendent go test processes that cannot talk to each other.
The address suggestion code, mostly used to find an open port, can
cause port collisions and a race condition between different envtests
running at the same time.

This change switches the internal memory to use a file based system that
creates a file.

Signed-off-by: Vince Prignano vincepri@vmware.com

[coderanger]

This would help specifically for parallel testing of one package but not multiple packages, right? Since those each get their own entrypoint binary so would be independent tempdirs?

[vincepri]

Are you referring to darwin?

[alvaroaleman]

Envtest is often running in parallel when using go test, which spins up
multiple indipendent go test processes

TILd

[coderanger]

Are you referring to darwin?

Looks like you took care of it with UserCacheDir, nice :)

[christopherhein]

Does this stop one test process from stopping envtest on test completion causing flakes across multiple packages?

[vincepri]

Does this stop one test process from stopping envtest on test completion causing flakes across multiple packages?

This stops a race condition that could happen in the event that the same port is allocated and closed quickly between two processes, where one end up not starting because either etcd or api-server is reusing a port.

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: alvaroaleman, vincepri

The full list of commands accepted by this bot can be found here.

The pull request process is described here

Needs approval from an approver in each of these files:

• OWNERS [alvaroaleman,vincepri]

Approvers can indicate their approval by writing /approve in a comment
Approvers can cancel approval by writing /approve cancel in a comment

[Porges]

@vincepri We just updated to controller-runtime@v0.9.2 and it looks like this code is causing problems for us. We run envtest in parallel and are getting test timeouts with goroutines sitting in unix.Flock; I am wondering if the acquire call should be made with LOCK_NB|LOCK_EX to ensure it doesn’t block?

[vincepri]

@Porges Thanks for the report, running some tests locally with the exclusive and non-blocking flags. Can you open an issue and give some more information on your environment, how many envtests are you running in parallel, and the information you found?