Instance gets stuck if parallel multi instance on call process has output mapping for all

Camunda 7 Topics Discussion & Questions
1

Dear Community,

I’ve discovered a problem when a process instance gets stuck if parallel multi instance (PMI) on call BPMN has output mapping for All variables. The loop cardinality for the PMI must be > 1. As soon as I remove the output mapping the instance completes successfully after all tasks from the called instances are completed.

Is this expected behavior or a defect?

Thank you!
Sergii

2

The repro is available at the following repository

3

Hi Sergii,

Thanks for the dedicated test case. Yes, it is a bug.

The problem is, that with <camunda:in variables="all" /> the variables nrOfInstances, nrOfActiveInstances, nrOfCompletedInstances and loopCounter (see 1) are handed over to the called process instance. Due to <camunda:out variables="all" /> the same variables are handed over back from the called process instance to the calling process instance, so that the values are overwritten in the calling process instance. Then the calling process instance stucks.

Instead of <camunda:in variables="all">, you could list all variables that must be handed over to called process instance. So that variables mentioned above are not passed to it.

I will create a bug ticket for that.

Cheers,
Roman

1 Like
4

Here is the bug ticket: https://app.camunda.com/jira/browse/CAM-5829

5

Thank you very much Roman for the detailed explanation, workaround and submitted defect!