Set parallelism for the parallelize job in recursiveListDirs #3708
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Which Delta project/connector is this regarding?
Description
DeltaFileOperations.recursiveListDirscallsparallelizewithout specifying the parallelism. Hence, it always uses the number of available cores on a cluster. When a cluster has many cores butsubDirsis small, it will launch many empty tasks.This PR makes a small change to use
subDirs.length.min(spark.sparkContext.defaultParallelism)as the parallelism so that whensubDirsis smaller than the number of available cores, it will not launch empty tasks.How was this patch tested?
Existing tests.
Does this PR introduce any user-facing changes?
No