I'm basically running a sorting using spark. The spark program will read from HDFS, sort on composite keys, and then save the partitioned result back to HDFS. pseudo code is like this:
input = sc.textFile pairs = input.mapToPair sorted = pairs.sortByKey values = sorted.values values.saveAsTextFile Input size is ~ 160G, and I made 1000 partitions specified in JavaSparkContext.textFile and JavaPairRDD.sortByKey. From WebUI, the job is splitted into two stages: saveAsTextFile and mapToPair. MapToPair finished in 8 mins. While saveAsTextFile took ~15mins to reach (2366/2373) progress and the last few jobs just took forever and never finishes. Cluster setup: 8 nodes on each node: 15gb memory, 8 cores running parameters: --executor-memory 12G --conf "spark.cores.max=60" Thank you for any help. -- View this message in context: http://apache-spark-user-list.1001560.n3.nabble.com/saveAsTextFile-extremely-slow-near-finish-tp21978.html Sent from the Apache Spark User List mailing list archive at Nabble.com. --------------------------------------------------------------------- To unsubscribe, e-mail: user-unsubscr...@spark.apache.org For additional commands, e-mail: user-h...@spark.apache.org
