You can stop or abort running workflow by one of the following ways:
Issuing stop of abort in the informatica workflow monitor
Issuing stop of abort command in pmcmd.
specifying in the control task.
Difference Between Stop and Abort:
When you run a session, it holds memory blocks in the OS. When issue a abort on the session, it kills the threads and leaves the memory blocks. This causes memory issues in the server and leads to poor performance. Some operating systems clean the lost memory blocks automatically. However most of the operating systems do not clean up these memory blocks. Stop is clean way of killing the sessions and cleans up the memory blocks.
You can either stop or abort a task within a workflow from the Workflow Monitor. Stopping a Task:
When you stop a task the Integration service stops processing the task The Integration Service does not process other tasks in the path of the stopped or aborted task. When we stop a task the Integration Service continues processing concurrent tasks in the workflow. If the Integration Service cannot stop the task, you can abort the task.
Aborting a Task:
Abort task is similar to stopping but the difference is that except it has a timeout period of 60 seconds. If the Integration Service cannot finish processing and committing data within the timeout period, it kills the DTM process and terminates the session When you abort a task, the Integration Service kills the process on the task(Just like the unix kill command) When you abort a task the Integration Service continues processing concurrent tasks.