Does spark.streaming.concurrentJobs still exist? spark.streaming.concurrentJobs (default: 1) is the number of concurrent jobs, i.e. threads in streaming-job-executor thread pool <https://github.com/jaceklaskowski/spark-streaming-notebook/blob/master/spark-streaming-jobscheduler.adoc#streaming-job-executor> .
Also how is this definition different from executor-cores?
