Github user squito commented on a diff in the pull request: https://github.com/apache/spark/pull/22371#discussion_r216387272 --- Diff: core/src/main/scala/org/apache/spark/shuffle/IndexShuffleBlockResolver.scala --- @@ -138,13 +154,22 @@ private[spark] class IndexShuffleBlockResolver( mapId: Int, lengths: Array[Long], dataTmp: File): Unit = { + val mapLocks = shuffleIdToLocks.get(shuffleId) + require(mapLocks != null, "Shuffle should be registered to IndexShuffleBlockResolver first") + val lock = mapLocks.synchronized { --- End diff -- in the usual case, multiple threads are still sharing the same shuffleID, they're just writing to different map tasks. (they are in the simple example job @ConeyLiu gave, of `spark.range(0, 10000000, 1, 100).repartition(200).count()`)
--- --------------------------------------------------------------------- To unsubscribe, e-mail: reviews-unsubscr...@spark.apache.org For additional commands, e-mail: reviews-h...@spark.apache.org