VScode breakpoint will be bypassed even with local_mode=True

Ray Libraries (Data, Train, Tune, Serve) Ray Train
1

How severe does this issue affect your experience of using Ray?

  • Medium: It contributes to significant difficulty to complete my task, but I can work around it.

I am writing a DL training framework that leverages Ray Train and Ray Tune. Unlike my previous experience with RLLib, VScode breakpoints that I set in Ray Train processes would be passed despite I set local_mode=True in Ray 2.1.0. Which forced me to use Ray Debug, which is not convenient for Test Driven Development.

Is this an expected behavior for Ray Train, or is it a bug? Or is there anything I missed?

2

Hi Team, is this a known issue? Or we have plan to allow synchronized debugging in Ray Train?

3

Hey @heng2j, sorry for the late response. Local_mode has been hard to maintain and I suspect it won’t work quite well with Ray Train.

A couple options for you include:

  1. Setting num_workers=0 or num_workers=1.
  2. Using Ray Debug.

I’d be curious about your experience with Ray Debug. What makes it inconvenient?

4

I am searching for a way to use the vscode debugger with Ray. I have used the ray debug mode, and while it works and is effective for quick checks, it lacks all modern QOL which reduces development speed by orders of magnitude:

  • Fast breakpoint deactivation/activation
  • Adding breakpoints during a live run
  • Interactive gui scope for quick variable interrogation
  • ability to copy paste multi line functions or loops without indentation considerations
  • simple things like being able to use the up arrow to re-execute and modify previous commands

Any chance vscode debugging will eventually be supported in Ray?

Cheers,

Robert