I’m calling multiple workflows from a wrapper workflow using POST Request node.When trying to invoke multiple (Child) workflows at a time with multiple request to wrapper workflow from external.
I’m finding an issue and noticed that few job instances created for the Wrapper workflow to invoke the respective child workflow is not executing. Once the child Workflow’s job is created, the response to the POST request node are not received back and thus I’m not able to get the job’s execution URL and I have not currently installed the RabbitMQ system in Server.
please help me on what causes this issue and how to resolve this.
I’ve understood you’re calling a wrapper workflow multiple times in quick succession, which in return itself starts multiple child workflows all at once.
In this setup, some of the child workflows do not start to execute.
In general, I’d suggest to distribute the load over time, where possible. There is a limit to the number of Jobs a single executor can load in parallel, which may be the bottleneck here, though other performance bottlenecks may come up. Maybe the wrapper workflow can be extended to be called only a single time but with a parameter of how often to run. It can then itself wait for the called workflows to complete, before running them again.
When you call KNIME Workflows from within a workflow, you can also use our dedicated Call Workflow Service node. This allows you to easily pass KNIME tables and other data as input and even retrieve the output of the child workflow in the parent/wrapper workflow. You will find a guide to using these features here: