VSCode Debugging breaks when opening a zarr container

[EuAtarax]

When debugging with VSCode and an open variable viewer, the debugging breaks/stalls whenever I open a HCS zarr plate (or normal container).
After some time spent on figuring the problem out, I suspect that it has to do with the async workers/threads and that one has the power over GIL.

Solution/Workaround (but not really):
When I collapse the variable viewer, the debugging does not stop and I have access to variables from the debug console. But as soon as I open the variable Viewer everything stalls.

Do you have solutions/workarounds?
Otherwise it might be worth thinking about exposing num_workers or maybe creating a Singleton.

Best,
Niklas

[lorenzocerrone]

Hi Niklas,

I wasn't able to reproduce it on my end. Could you share a small code snippet that triggers the issue?

I tried a simple debug session like this:

And it all seemed to work fine.

About the threading, ngio's normal container doesn't use async, but zarr-python does under the hood, so the GIL contention is likely coming from there. You can tweak zarr's async config via zarr.config (see the config docs), in particular the async.concurrency and threading.max_workers keys.

If that fixes it, I can look into exposing some similar configs for the Plate Container that uses async directly.

Best,
Lorenzo