pyspark - How costly is unpersist operation on spark RDDs? -


i wondering, how costly can berdd.unpersist() operation on spark rdds ?, , storage level setting impact performance of operation ? benchmark(results/technique) full.

unpersist releases rdd cache (memory , disk) , deletes shuffle files depends on. needs send message executors. should cheapest operation can rdd — not worth benchmarking.

note when rdd garbage collected, unpersist automatically called on it. cannot avoid cost anyway.


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