3
votes

I have a maven scala application that submits a spark job to Spark standalone single node cluster. When job is submitted, Spark application tries to access cassandra, which is hosted on Amazon EC2 instance, using spark-cassandra-connector. Connection is established, but results are not returned. After some time connector disconnects. It works fine if I'm running spark in local mode. I tried to create simple application and my code looks like this:

val sc = SparkContextLoader.getSC
def runSparkJob():Unit={
   val table =sc.cassandraTable("prosolo_logs_zj", "logevents")
   println(table.collect().mkString("\n"))
}

SparkContext.scala

 object SparkContextLoader {    
  val sparkConf = new SparkConf()
  sparkConf.setMaster("spark://127.0.1.1:7077")

  sparkConf.set("spark.cores_max","2")
  sparkConf.set("spark.executor.memory","2g")
  sparkConf.set("spark.serializer", "org.apache.spark.serializer.KryoSerializer")
  sparkConf.setAppName("Test application")
  sparkConf.set("spark.cassandra.connection.host", "xxx.xxx.xxx.xxx")
  sparkConf.set("spark.cassandra.connection.port", "9042")
  sparkConf.set("spark.ui.port","4041")

   val oneJar="/samplesparkmaven/target/samplesparkmaven-jar.jar"
    sparkConf.setJars(List(oneJar))
   @transient  val sc = new SparkContext(sparkConf)

}

Console output looks like:

Using Spark's default log4j profile: org/apache/spark/log4j-defaults.properties
17/02/14 23:11:25 INFO SparkContext: Running Spark version 2.1.0
17/02/14 23:11:26 WARN NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable
17/02/14 23:11:27 WARN Utils: Your hostname, zoran-Latitude-E5420 resolves to a loopback address: 127.0.1.1; using 192.168.2.68 instead (on interface wlp2s0)
17/02/14 23:11:27 WARN Utils: Set SPARK_LOCAL_IP if you need to bind to another address
17/02/14 23:11:27 INFO SecurityManager: Changing view acls to: zoran
17/02/14 23:11:27 INFO SecurityManager: Changing modify acls to: zoran
17/02/14 23:11:27 INFO SecurityManager: Changing view acls groups to: 
17/02/14 23:11:27 INFO SecurityManager: Changing modify acls groups to: 
17/02/14 23:11:27 INFO SecurityManager: SecurityManager: authentication disabled; ui acls disabled; users  with view permissions: Set(zoran); groups with view permissions: Set(); users  with modify permissions: Set(zoran); groups with modify permissions: Set()
17/02/14 23:11:28 INFO Utils: Successfully started service 'sparkDriver' on port 33995.
17/02/14 23:11:28 INFO SparkEnv: Registering MapOutputTracker
17/02/14 23:11:28 INFO SparkEnv: Registering BlockManagerMaster
17/02/14 23:11:28 INFO BlockManagerMasterEndpoint: Using org.apache.spark.storage.DefaultTopologyMapper for getting topology information
17/02/14 23:11:28 INFO BlockManagerMasterEndpoint: BlockManagerMasterEndpoint up
17/02/14 23:11:28 INFO DiskBlockManager: Created local directory at /tmp/blockmgr-7b25a4cc-cb37-4332-a59b-e36fa45511cd
17/02/14 23:11:28 INFO MemoryStore: MemoryStore started with capacity 870.9 MB
17/02/14 23:11:28 INFO SparkEnv: Registering OutputCommitCoordinator
17/02/14 23:11:28 INFO Utils: Successfully started service 'SparkUI' on port 4041.
17/02/14 23:11:28 INFO SparkUI: Bound SparkUI to 0.0.0.0, and started at http://192.168.2.68:4041
17/02/14 23:11:28 INFO SparkContext: Added JAR /samplesparkmaven/target/samplesparkmaven-jar.jar at spark://192.168.2.68:33995/jars/samplesparkmaven-jar.jar with timestamp 1487142688817
17/02/14 23:11:28 INFO StandaloneAppClient$ClientEndpoint: Connecting to master spark://127.0.1.1:7077...
17/02/14 23:11:28 INFO TransportClientFactory: Successfully created connection to /127.0.1.1:7077 after 62 ms (0 ms spent in bootstraps)
17/02/14 23:11:29 INFO StandaloneSchedulerBackend: Connected to Spark cluster with app ID app-20170214231129-0016
17/02/14 23:11:29 INFO Utils: Successfully started service 'org.apache.spark.network.netty.NettyBlockTransferService' on port 36901.
17/02/14 23:11:29 INFO NettyBlockTransferService: Server created on 192.168.2.68:36901
17/02/14 23:11:29 INFO BlockManager: Using org.apache.spark.storage.RandomBlockReplicationPolicy for block replication policy
17/02/14 23:11:29 INFO BlockManagerMaster: Registering BlockManager BlockManagerId(driver, 192.168.2.68, 36901, None)
17/02/14 23:11:29 INFO BlockManagerMasterEndpoint: Registering block manager 192.168.2.68:36901 with 870.9 MB RAM, BlockManagerId(driver, 192.168.2.68, 36901, None)
17/02/14 23:11:29 INFO BlockManagerMaster: Registered BlockManager BlockManagerId(driver, 192.168.2.68, 36901, None)
17/02/14 23:11:29 INFO BlockManager: Initialized BlockManager: BlockManagerId(driver, 192.168.2.68, 36901, None)
17/02/14 23:11:29 INFO StandaloneSchedulerBackend: SchedulerBackend is ready for scheduling beginning after reached minRegisteredResourcesRatio: 0.0
17/02/14 23:11:29 INFO NettyUtil: Found Netty's native epoll transport in the classpath, using it
17/02/14 23:11:31 INFO Cluster: New Cassandra host /xxx.xxx.xxx.xxx:9042 added
17/02/14 23:11:31 INFO CassandraConnector: Connected to Cassandra cluster: Test Cluster
17/02/14 23:11:32 INFO SparkContext: Starting job: collect at SparkConnector.scala:28
17/02/14 23:11:32 INFO DAGScheduler: Got job 0 (collect at SparkConnector.scala:28) with 6 output partitions
17/02/14 23:11:32 INFO DAGScheduler: Final stage: ResultStage 0 (collect at SparkConnector.scala:28)
17/02/14 23:11:32 INFO DAGScheduler: Parents of final stage: List()
17/02/14 23:11:32 INFO DAGScheduler: Missing parents: List()
17/02/14 23:11:32 INFO DAGScheduler: Submitting ResultStage 0 (CassandraTableScanRDD[0] at RDD at CassandraRDD.scala:18), which has no missing parents
17/02/14 23:11:32 INFO MemoryStore: Block broadcast_0 stored as values in memory (estimated size 8.4 KB, free 870.9 MB)
17/02/14 23:11:32 INFO MemoryStore: Block broadcast_0_piece0 stored as bytes in memory (estimated size 4.4 KB, free 870.9 MB)
17/02/14 23:11:32 INFO BlockManagerInfo: Added broadcast_0_piece0 in memory on 192.168.2.68:36901 (size: 4.4 KB, free: 870.9 MB)
17/02/14 23:11:32 INFO SparkContext: Created broadcast 0 from broadcast at DAGScheduler.scala:996
17/02/14 23:11:32 INFO DAGScheduler: Submitting 6 missing tasks from ResultStage 0 (CassandraTableScanRDD[0] at RDD at CassandraRDD.scala:18)
17/02/14 23:11:32 INFO TaskSchedulerImpl: Adding task set 0.0 with 6 tasks
17/02/14 23:11:39 INFO CassandraConnector: Disconnected from Cassandra cluster: Test Cluster

I'm using

  • scala 2.11.6
  • spark 2.1.0 (both for standalone spark and dependency in application)
  • spark-cassandra-connector 2.0.0-M3
  • Cassandra Java driver 3.0.0
  • Apache Cassandra 3.9

Version compatibility table for cassandra connector doesn't show any problem with it, but I can't figure out anything else that might be the problem.

1

1 Answers

1
votes

I've finally solved the problem I had. It turned out to be the problem with path. I was using local path to the jar, but missed to add "." at the beginning, so it was treated as absolute path. Unfortunately, there was no exception in the application indicating that file doesn't exist on the provided path, and the only exception I had was from the worker which could not find jar file in the Spark cluster.