我试图从1.2版本使用新的连接功能,但我得到repl的repartitionByCassandraReplica函数的错误。cassandra火花连接器错误与repartitionByCassandraReplica函数
我试图复制网站的例子,一对夫妇的元素创造了一个卡桑德拉表(shopping_history): https://github.com/datastax/spark-cassandra-connector/blob/master/doc/2_loading.mde
import com.datastax.spark.connector.rdd._
import com.datastax.spark.connector.cql.CassandraConnector
import com.datastax.spark.connector._
import com.datastax.driver.core._
case class CustomerID(cust_id: Int)
val idsOfInterest = sc.parallelize(1 to 1000).map(CustomerID(_))
val repartitioned = idsOfInterest.repartitionByCassandraReplica("cim_dev", "shopping_history", 10)
repartitioned.first()
我得到这个错误:
15/04/13 18:35:43 WARN TaskSetManager: Lost task 0.0 in stage 1.0 (TID 2, dev2-cim.aid.fr): java.lang.ClassNotFoundException: $line31.$read$$iwC$$iwC$CustomerID
at java.net.URLClassLoader$1.run(URLClassLoader.java:372)
at java.net.URLClassLoader$1.run(URLClassLoader.java:361)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:360)
at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:344)
at org.apache.spark.serializer.JavaDeserializationStream$$anon$1.resolveClass(JavaSerializer.scala:59)
at java.io.ObjectInputStream.readNonProxyDesc(ObjectInputStream.java:1613)
at java.io.ObjectInputStream.readClassDesc(ObjectInputStream.java:1518)
at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1774)
at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1351)
at java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:1993)
at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1918)
at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1801)
at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1351)
at java.io.ObjectInputStream.readObject(ObjectInputStream.java:371)
at org.apache.spark.serializer.JavaDeserializationStream.readObject(JavaSerializer.scala:62)
at org.apache.spark.serializer.DeserializationStream$$anon$1.getNext(Serializer.scala:133)
at org.apache.spark.util.NextIterator.hasNext(NextIterator.scala:71)
at org.apache.spark.util.CompletionIterator.hasNext(CompletionIterator.scala:32)
at scala.collection.Iterator$$anon$13.hasNext(Iterator.scala:371)
at org.apache.spark.util.CompletionIterator.hasNext(CompletionIterator.scala:32)
at org.apache.spark.InterruptibleIterator.hasNext(InterruptibleIterator.scala:39)
at scala.collection.Iterator$$anon$11.hasNext(Iterator.scala:327)
at scala.collection.Iterator$$anon$11.hasNext(Iterator.scala:327)
at scala.collection.Iterator$$anon$10.hasNext(Iterator.scala:308)
at scala.collection.Iterator$class.foreach(Iterator.scala:727)
at scala.collection.AbstractIterator.foreach(Iterator.scala:1157)
at scala.collection.generic.Growable$class.$plus$plus$eq(Growable.scala:48)
at scala.collection.mutable.ArrayBuffer.$plus$plus$eq(ArrayBuffer.scala:103)
at scala.collection.mutable.ArrayBuffer.$plus$plus$eq(ArrayBuffer.scala:47)
at scala.collection.TraversableOnce$class.to(TraversableOnce.scala:273)
at scala.collection.AbstractIterator.to(Iterator.scala:1157)
at scala.collection.TraversableOnce$class.toBuffer(TraversableOnce.scala:265)
at scala.collection.AbstractIterator.toBuffer(Iterator.scala:1157)
at scala.collection.TraversableOnce$class.toArray(TraversableOnce.scala:252)
at scala.collection.AbstractIterator.toArray(Iterator.scala:1157)
at org.apache.spark.rdd.RDD$$anonfun$27.apply(RDD.scala:1098)
at org.apache.spark.rdd.RDD$$anonfun$27.apply(RDD.scala:1098)
at org.apache.spark.SparkContext$$anonfun$runJob$4.apply(SparkContext.scala:1353)
at org.apache.spark.SparkContext$$anonfun$runJob$4.apply(SparkContext.scala:1353)
at org.apache.spark.scheduler.ResultTask.runTask(ResultTask.scala:61)
at org.apache.spark.scheduler.Task.run(Task.scala:56)
at org.apache.spark.executor.Executor$TaskRunner.run(Executor.scala:200)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at java.lang.Thread.run(Thread.java:745)
我使用spark 1.2.0和connector 1.2.0 RC 3. idsOfInterest上使用的joinWithCassandraTable函数可以工作。
我也很好奇joinWithCassandraTable/cassandraTable与In子句/ foreachPartition(withSessionDo)语法之间的区别。
它们是否都将数据请求到作为协调器的本地节点? joinWithCassandraTable与repartitionByCassandraReplica结合如同异步查询一样高效,仅向本地节点请求数据?如果不应用repartitionByCassandraReplica会发生什么情况?
我已经问过这个问题上卡桑德拉连接器的谷歌小组论坛: https://groups.google.com/a/lists.datastax.com/forum/#!topic/spark-connector-user/b615ANGSySc
感谢
我不知道你的类加载器的问题,不知道你是如何运行这个代码,你可以给我们提交你的提交命令或启动命令吗? – RussS
@RussS,我的启动命令是spark-shell :),其中spark.executor.extraClassPath/spark.driver.extraClassPath在spark-default.conf中设置到cassandra连接器jar中。奇怪的是,找不到的类是在shell中创建的... – Alex
使用完整的程序集?另外尝试--jar有时会在某些版本的spark上出现一些classloader怪异。 – RussS