In my workflow I have two activities running in parallel. I then sleep the workflow for 10 seconds. During this time, is the spawned activity still running? Additionally, after 10 seconds the same two activities are executed again. Will this affect the execution of the prior activities?
Yes, they are executed in a different thread, or even in a different worker. If you need to sleep an activity, you have to do it within the activity code.
No, if the activity implementation is thread-safe. Since you are registering a single activity instance per worker the same activity instance is reused