Issue in maximum active workflow instances

Hi team,
I am currently using self managed temporal as part of a POC project. What I observe is upon initiating multiple workflows at a time, only 8 workflow instances are seen active at a time.
I have also given the following in worker options:

WorkerFactoryOptions options = WorkerFactoryOptions.newBuilder()
			    .setMaxWorkflowThreadCount(500)
			    .build();

The number of shards is set to 512 in cluster’s configuration but still maximum concurrent execution is limited only to 8. Could you please help me to figure out the reason for this.

Hi, lets work off the previous request Issue facing during creation of large number of workflows - #5 by tihomir if possible so we don’t duplicate efforts. Thanks