Flink: Jar file execution on Flink cluster

Question

I am using the flink cluster with 9 task managers on 2 different physical nodes. When i submit the jar to the Jobmanager(Master) of Flink, what does exactly happen to the jar. I mean, does the jar get distributed to all worker nodes or some part of the function gets reaplicated to all working nodes?

I am asking this because, when I trying to run my application, it is running locally successfully, but give an error of serialization on FlatMapFunction when subject to run on cluster.

Answer 1

Job Manager process application code, split it to tasks and subtasks and send them to one or more(depending on task parallelism) execution slots in task managers. From the Flink documentation :

Each worker (TaskManager) is a JVM process, and may execute one or more subtasks in separate threads. To control how many tasks a worker accepts, a worker has so called task slots (at least one).]