Herman Schistad created SPARK-13198: ---------------------------------------
Summary: sc.stop() does not clean up on driver, causes Java heap OOM. Key: SPARK-13198 URL: https://issues.apache.org/jira/browse/SPARK-13198 Project: Spark Issue Type: Bug Components: Mesos Affects Versions: 1.6.0 Reporter: Herman Schistad When starting and stopping multiple SparkContext's linearly eventually the driver stops working with a "io.netty.handler.codec.EncoderException: java.lang.OutOfMemoryError: Java heap space" error. Reproduce by running the following code and loading in ~7MB parquet data each time. The driver heap space is not changed and thus defaults to 1GB: {code:java} def main(args: Array[String]) { val conf = new SparkConf().setMaster("MASTER_URL").setAppName("") conf.set("spark.mesos.coarse", "true") conf.set("spark.cores.max", "10") for (i <- 1 until 100) { val sc = new SparkContext(conf) val sqlContext = new SQLContext(sc) val events = sqlContext.read.parquet("hdfs://locahost/tmp/something") println(s"Context ($i), number of events: " + events.count) sc.stop() } } {code} The heap space fills up within 20 loops on my cluster. Increasing the number of cores to 50 in the above example results in heap space error after 12 contexts. Dumping the heap reveals many equally sized "CoarseMesosSchedulerBackend" objects (see attachments). Digging into the inner objects tells me that the `executorDataMap` is where 99% of the data in said object is stored. I do believe though that this is beside the point as I'd expect this whole object to be garbage collected or freed on sc.stop(). Additionally I can see in the Spark web UI that each time a new context is created the number of the "SQL" tab increments by one (i.e. last iteration would have SQL99). After doing stop and creating a completely new context I was expecting this number to be reset to 1 ("SQL"). I'm submitting the jar file with `spark-submit` and no special flags. The cluster is running Mesos 0.23. I'm running Spark 1.6.0. -- 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