Pluto hangs when using MATLAB.jl

[fcdimitr]

Pluto hangs when using MATLAB.jl

Pluto notebook that calls MATLAB commands runs indefinitely. Perhaps it is an issue with parsing the terminal output?

Minimum example: https://gist.github.com/fcdimitr/c48cc6f6c4764a61b555f0c985bf76c0

I noticed the issue with version v0.18.4, it was working with v0.18.0

[disberd]

I just tried running your notebook on latest Pluto and I don't notice this:

Edit: I am on windows 10 with Julia 1.7.1 and using Chrome

[fcdimitr]

Thank you for testing it on Windows!

The issue appears on my side on both Linux (Ubuntu) and macOS 11 (Monterey).

I do not have access to a Windows machine to try it.

Edit: I was using Safari and Julia v1.7.2

[fcdimitr]

I am retesting with a simpler version; only trying to start a MATLAB session with a 0-length buffer to store MATLAB output text:

using MATLAB
MATLAB.default_msession_ref[] = MSession(0; flags="-nodisplay -nosplash -nodesktop");

This command alone freezes Pluto indefinitely on macOS with Julia v1.7.2

The same command works as expected through REPL.

[fcdimitr]

Thanks to @lungben for the following workaround:

You could try to deactivate multiprocessing in Pluto: https://github.com/fonsp/Pluto.jl/blob/15a94f415dba4fbad753ddac5153fa9286ce0eb2/src/Configuration.jl#L106 Pluto.run(workspace_use_distributed=false)

[fonsp]

Might be linked to #2001. I believe that disabling workspace_use_distributed will also disable terminal forwarding, which would explain why it fixes the problem.

[fonsp]

I don't have a matlab license so it won't be easy for me to work on this. @fcdimitr be sure to subscribe to #2001, if we make a candidate PR to fix that issue, try it out on the matlab notebook.

[fcdimitr]

Disabling output forwarding, via #2022, resolved the issue on my side.