问题
执行spark-submit报错ERROR MapOutputTracker:70 - Missing an output location for shuffle 176和Job aborted due to stage failure: ShuffleMapStage 512 (map at MovieLensALS.scala:144) has failed the maximum allowable number of times: 4.
解决
更改分区:spark-submit命令后加上--conf spark.sql.shuffle.partitions=520，具体数字取决于报错提示
