Hi All, I am here to get some expert advice on a use case I am working on. Cluster & job details below -
Data - 6 Tb Cluster - EMR - 15 Nodes C3-8xLarge (shared by other MR apps) Parameters- --executor-memory 10G \ --executor-cores 6 \ --conf spark.dynamicAllocation.enabled=true \ --conf spark.dynamicAllocation.initialExecutors=15 \ Runtime : 3 Hrs On monitoring the metrics I notices 10G for executors is not required (since I don't have lot of groupings) Reducing to --executor-memory 3G, Runtime reduced to: 2 Hrs Question: On adding more nodes now has absolutely no effect on the runtime. Is there anything I can tune/change/experiment with to make the job faster. Workload: Mostly reduceBy's and scans. Would appreciate any insights and thoughts. Best Regards