Question

spark 2.4.2可以与Amazon EMR上的蜂巢2.3.4一起用作执行引擎吗？

我通过以下命令将jar文件与hive（scala库，spark-core，spark-common-network）链接在一起：

cd $HIVE_HOME/lib
ln -s $SPARK_HOME/jars/spark-network-common_2.11-2.4.2.jar
ln -s $SPARK_HOME/jars/spark-core_2.11-2.4.2.jar
ln -s $SPARK_HOME/jars/scala-library-2.11.12.jar

在hive-site.xml中添加了以下设置：

<property>
    <name>hive.execution.engine</name>
    <value>spark</value>
    <description>Use Map Reduce as default execution engine</description>
</property>
<property>
    <name>spark.master</name>
    <value>spark://<EMR hostname>:7077</value>
  </property>
<property>
    <name>spark.eventLog.enabled</name>
    <value>true</value>
  </property>
<property>
    <name>spark.eventLog.dir</name>
    <value>/tmp</value>
  </property>
<property>
    <name>spark.serializer</name>
    <value>org.apache.spark.serializer.KryoSerializer</value>
  </property>
<property>
  <name>spark.yarn.jars</name>
  <value>hdfs://<EMR hostname>:54310/spark-jars/*</value>
</property>

Spark已启动并正在运行，我还可以在pyspark中使用配置单元查询。但是，当我尝试将Spark用作具有上述配置的蜂巢的执行引擎时，会引发以下错误：

Exception in thread "main" java.lang.NoClassDefFoundError: scala/collection/Iterable
    at org.apache.hadoop.hive.ql.optimizer.spark.SetSparkReducerParallelism.getSparkMemoryAndCores(SetSparkReducerParallelism.java:236)
    at org.apache.hadoop.hive.ql.optimizer.spark.SetSparkReducerParallelism.process(SetSparkReducerParallelism.java:173)
    at org.apache.hadoop.hive.ql.lib.DefaultRuleDispatcher.dispatch(DefaultRuleDispatcher.java:90)
    at org.apache.hadoop.hive.ql.lib.DefaultGraphWalker.dispatchAndReturn(DefaultGraphWalker.java:105)
    at org.apache.hadoop.hive.ql.lib.DefaultGraphWalker.dispatch(DefaultGraphWalker.java:89)
    at org.apache.hadoop.hive.ql.lib.PreOrderWalker.walk(PreOrderWalker.java:56)
    at org.apache.hadoop.hive.ql.lib.PreOrderWalker.walk(PreOrderWalker.java:61)
    at org.apache.hadoop.hive.ql.lib.PreOrderWalker.walk(PreOrderWalker.java:61)
    at org.apache.hadoop.hive.ql.lib.PreOrderWalker.walk(PreOrderWalker.java:61)
    at org.apache.hadoop.hive.ql.lib.DefaultGraphWalker.startWalking(DefaultGraphWalker.java:120)
    at org.apache.hadoop.hive.ql.parse.spark.SparkCompiler.runSetReducerParallelism(SparkCompiler.java:288)
    at org.apache.hadoop.hive.ql.parse.spark.SparkCompiler.optimizeOperatorPlan(SparkCompiler.java:122)
    at org.apache.hadoop.hive.ql.parse.TaskCompiler.compile(TaskCompiler.java:140)
    at org.apache.hadoop.hive.ql.parse.SemanticAnalyzer.analyzeInternal(SemanticAnalyzer.java:11293)
    at org.apache.hadoop.hive.ql.parse.CalcitePlanner.analyzeInternal(CalcitePlanner.java:286)
    at org.apache.hadoop.hive.ql.parse.BaseSemanticAnalyzer.analyze(BaseSemanticAnalyzer.java:258)
    at org.apache.hadoop.hive.ql.Driver.compile(Driver.java:512)
    at org.apache.hadoop.hive.ql.Driver.compileInternal(Driver.java:1317)
    at org.apache.hadoop.hive.ql.Driver.runInternal(Driver.java:1457)
    at org.apache.hadoop.hive.ql.Driver.run(Driver.java:1237)
    at org.apache.hadoop.hive.ql.Driver.run(Driver.java:1227)
    at org.apache.hadoop.hive.cli.CliDriver.processLocalCmd(CliDriver.java:233)
    at org.apache.hadoop.hive.cli.CliDriver.processCmd(CliDriver.java:184)
    at org.apache.hadoop.hive.cli.CliDriver.processLine(CliDriver.java:403)
    at org.apache.hadoop.hive.cli.CliDriver.executeDriver(CliDriver.java:821)
    at org.apache.hadoop.hive.cli.CliDriver.run(CliDriver.java:759)
    at org.apache.hadoop.hive.cli.CliDriver.main(CliDriver.java:686)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at org.apache.hadoop.util.RunJar.run(RunJar.java:239)
    at org.apache.hadoop.util.RunJar.main(RunJar.java:153)
Caused by: java.lang.ClassNotFoundException: scala.collection.Iterable
    at java.net.URLClassLoader.findClass(URLClassLoader.java:382)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
    at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:349)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
    ... 33 more

这是配置错误还是某些版本不兼容错误？

蜂巢还可以与tez完美配合...

Answer 1

这清楚地表明配置单元使用的Scala jar库不匹配，因为您正在为带有Spark选项的配置单元使用不兼容的Scala更改。

Tez不使用spark和scala，这就是其正常工作的原因。 spark正在使用scala作为lang，但无法找到正确的版本。多数民众赞成在这个原因

java.lang.NoClassDefFoundError: scala/collection/Iterable

当您将带有hive的配置单元用作执行引擎时，这是一个非常常见的问题...

步骤： 。

1）转到$ HIVE_HOME / bin / hive

2）在编辑$ HIVE_HOME / bin / hive之前先备份文件
3）取得classpath变量，然后首先添加所有配置单元

CLASSPATH=${CLASSPATH}:${HIVE_LIB}/*.jar
for f in ${HIVE_LIB}/*.jar; do
    CLASSPATH=${CLASSPATH}:$f;
done

将火花库添加到hive类路径中，就像下面的classpath变量一样，该变量具有所有hive库。.

for f in ${SPARK_HOME}/jars/*.jar; do
     CLASSPATH=${CLASSPATH}:$f;
done

现在，在同一个classpath变量中有蜂巢jar和spark jar。 Spark jars具有Scala库，可以正确地与spark一起使用，并且没有版本兼容性问题。

3）现在，更改hive执行引擎，使其指向您已经知道的hive-site.xml中的spark ... /做

<property>
    <name>hive.execution.engine</name>
    <value>spark</value>
    <description>Use Map Reduce as default execution engine</description>
</property>

另一个选择是使用软链接，例如下面的示例...

Link Jar Files 现在我们建立到某些Spark jar文件的软链接，以便Hive可以找到它们：

ln -s /usr/share/spark/spark-2.2.0/dist/jars/spark-network-common_2.11-2.2.0.jar /usr/local/hive/apache-hive-2.3.0-bin/lib/spark-network-common_2.11-2.2.0.jar
ln -s /usr/share/spark/spark-2.2.0/dist/jars/spark-core_2.11-2.2.0.jar /usr/local/hive/apache-hive-2.3.0-bin/lib/spark-core_2.11-2.2.0.jar
ln -s /usr/share/spark/spark-2.2.0/dist/jars/scala-library-2.11.8.jar /usr/local/hive/apache-hive-2.3.0-bin/lib/scala-library-2.11.8.jar

结论：无论如何，您都需要确保正确的scala jar指向由spark用作执行引擎的配置单元...

使用Hive作为Spark执行引擎

1 个答案: