Are you talking here of Spark SQL ?
If yes, spark.sql.shuffle.partitions needs to be changed.
I am running a Spark application setting the number of executor cores 1 and a default parallelism of 32 over 8 physical nodes.
The web UI shows it's running on 200 cores. I can't relate this number to the parameters I've used. How can I control the parallelism in a more deterministic way?
Saliya Ekanayake, Ph.D
Applied Computer Scientist
Network Dynamics and Simulation Science Laboratory (NDSSL)
Virginia Tech, Blacksburg
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