How to close APDL instance with PyMAPDL if something goes wrong...

I am developing a PyMAPDL script that has mistakes in it (it's a work in progress!) and when I run it, it keeps crashing out before the code can reach mapdl.exit(). This means that my spun-up MAPDL instance remains hanging and I have to kill it manually via task manager.

I want to write a function using atexit that can exit MAPDL sensibly. However, I may not have access to the mapdl object.

I am running the code in a script like the following:

try:
    func()
except Exception as error:
    print(Exception(error))
    raise

In this case func() contains the mapdl object generated from launch_mapdl(). Can I get it using any PyMAPDL commands and close any hanging MAPDL instances on exit?

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Comments

Camille

Hi James,

Thank you for raising this question.

The easiest solution I have in mind would be to use the PyMAPDL CLI mapdl stop, or mapdl stop --all if you have multiple opened instances, from your terminal.

You can find documentation about it at the following link.

Let me know if it solves your issue or if you have any constraints that prevent you from using the CLI.

James Derrick

the CLI is a good way to do it broadly, but I'd like to do it within the code as I'm actually running tests on PyMAPDL code that I can't change (they're being dynamically generated, by other scripts).

And there are upwards of 25 scripts, each being tested 2-3 times, which means that I'm going to end up with nearly 100 instances of MAPDL running at once if I'm not careful. It would be better to have something I can put in the code to kill the sessions as I go.

German Martinez

You could try to reconnect to the already alive instance, which is faster. If you cannot, you could relaunch it.

try:
    func()
    return # Exit if everything went OK. Assuming this is a decorator or similar
except MapdlExited as err:
    # attempt to reconnect
    pass
except Exception as error:
    print(Exception(error))
    raise error

# Reconnect
try:
     return launch_mapdl(start_instance=False, port=PORT)
except MapdlConnectionError:
    # Mapdl is dead, relaunch
    pass
except Exception as err:
     raise err

# relaunch
return launch_mapdl(start_instance=True, port=PORT