Stopping student projects is very flaky

[novoselt]

I am trying it as a test on a test severs, but I see the same thing in production with courses having just 6 or 4 students:

• I start all projects and it more or less works. I have projects open so I can see the state on tabs too.
• I click "Stop all..." and student projects start to change state, even getting to being stopped, but then they are started again for some reason.
• The status gets stuck at "3 of 4 student projects currently running."

My random guess is that the message to stop projects is sent, then there is some polling/waiting to see when the projects will actually stop. For some reason, they start again without a notice that they were stopped by that waiting process. So now student projects are running and don't plan to do anything else, but the course file is waiting for them to stop, without doing any actions to stop them further.

If I am right, then the best thing is to prevent project restart (put a lock on it to prohibit restart for say 30 seconds?). As a workaround, it is possible to keep sending "stop messages" until the project actually stops.