[ https://issues.apache.org/jira/browse/SPARK-7970?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Andrew Or updated SPARK-7970: ----------------------------- Assignee: Nitin Goyal Target Version/s: 1.6.0 > Optimize code for SQL queries fired on Union of RDDs (closure cleaner) > ---------------------------------------------------------------------- > > Key: SPARK-7970 > URL: https://issues.apache.org/jira/browse/SPARK-7970 > Project: Spark > Issue Type: Improvement > Components: Spark Core, SQL > Affects Versions: 1.2.0, 1.3.0 > Reporter: Nitin Goyal > Assignee: Nitin Goyal > Attachments: Screen Shot 2015-05-27 at 11.01.03 pm.png, Screen Shot > 2015-05-27 at 11.07.02 pm.png > > > Closure cleaner slows down the execution of Spark SQL queries fired on union > of RDDs. The time increases linearly at driver side with number of RDDs > unioned. Refer following thread for more context :- > http://apache-spark-developers-list.1001551.n3.nabble.com/ClosureCleaner-slowing-down-Spark-SQL-queries-tt12466.html > As can be seen in attached screenshots of Jprofiler, lot of time is getting > consumed in "getClassReader" method of ClosureCleaner and rest in > "ensureSerializable" (atleast in my case) > This can be fixed in two ways (as per my current understanding) :- > 1. Fixed at Spark SQL level - As pointed out by yhuai, we can create > MapPartitionsRDD idirectly nstead of doing rdd.mapPartitions which calls > ClosureCleaner clean method (See PR - > https://github.com/apache/spark/pull/6256). > 2. Fix at Spark core level - > (i) Make "checkSerializable" property driven in SparkContext's clean method > (ii) Somehow cache classreader for last 'n' classes -- This message was sent by Atlassian JIRA (v6.3.4#6332) --------------------------------------------------------------------- To unsubscribe, e-mail: issues-unsubscr...@spark.apache.org For additional commands, e-mail: issues-h...@spark.apache.org