在 DSE 4.8.4 上使用“dse spark-submit”的 netty/epoll 错误

Question

我们在 DSE 4.8.4 上使用“dse spark-submit”来处理 Spark/Scala 应用程序：

scalaVersion := "2.10.5"

libraryDependencies ++= Seq("org.apache.spark" %% "spark-core" % "1.4.1",
    "com.datastax.spark" %% "spark-cassandra-connector" % "1.4.1",
    "org.slf4j" % "slf4j-api" % "1.7.12",
    "org.slf4j" % "slf4j-simple" % "1.7.12"
)

自从我们从 DSE 4.8.2 更新到 4.8.4 后，我们看到了以下错误：

WARN  2016-02-11 10:48:23 com.datastax.driver.core.NettyUtil: Found Netty's native epoll transport in the classpath, but epoll is not available. Using NIO instead.
java.lang.UnsatisfiedLinkError: /tmp/libnetty-transport-native-epoll247904978292289355.so: /lib64/libc.so.6: version `GLIBC_2.14' not found (required by /tmp/libnetty-transport-native-epoll247904978292289355.so)
at java.lang.ClassLoader$NativeLibrary.load(Native Method) ~[na:1.8.0_65]
at java.lang.ClassLoader.loadLibrary0(Unknown Source) ~[na:1.8.0_65]
at java.lang.ClassLoader.loadLibrary(Unknown Source) ~[na:1.8.0_65]
at java.lang.Runtime.load0(Unknown Source) ~[na:1.8.0_65]
at java.lang.System.load(Unknown Source) ~[na:1.8.0_65]
at io.netty.util.internal.NativeLibraryLoader.load(NativeLibraryLoader.java:193) ~[netty-all-4.0.33.dse.jar:4.0.33.dse]
at io.netty.channel.epoll.Native.<clinit>(Native.java:48) ~[netty-all-4.0.33.dse.jar:4.0.33.dse]
at io.netty.channel.epoll.Epoll.<clinit>(Epoll.java:32) ~[netty-all-4.0.33.dse.jar:4.0.33.dse]
at java.lang.Class.forName0(Native Method) ~[na:1.8.0_65]
at java.lang.Class.forName(Unknown Source) ~[na:1.8.0_65]
at com.datastax.driver.core.NettyUtil.<clinit>(NettyUtil.java:68) ~[cassandra-driver-core-2.1.7.1.jar:na]
at com.datastax.driver.core.NettyOptions.eventLoopGroup(NettyOptions.java:101) [cassandra-driver-core-2.1.7.1.jar:na]
at com.datastax.driver.core.Connection$Factory.<init>(Connection.java:695) [cassandra-driver-core-2.1.7.1.jar:na]
at com.datastax.driver.core.Cluster$Manager.init(Cluster.java:1286) [cassandra-driver-core-2.1.7.1.jar:na]
at com.datastax.driver.core.Cluster.getMetadata(Cluster.java:339) [cassandra-driver-core-2.1.7.1.jar:na]
at com.datastax.spark.connector.cql.CassandraConnector$.com$datastax$spark$connector$cql$CassandraConnector$$createSession(CassandraConnector.scala:157) [spark-cassandra-connector_2.10-1.4.1.jar:1.4.1]
at com.datastax.spark.connector.cql.CassandraConnector$$anonfun$2.apply(CassandraConnector.scala:150) [spark-cassandra-connector_2.10-1.4.1.jar:1.4.1]
at com.datastax.spark.connector.cql.CassandraConnector$$anonfun$2.apply(CassandraConnector.scala:150) [spark-cassandra-connector_2.10-1.4.1.jar:1.4.1]
at com.datastax.spark.connector.cql.RefCountedCache.createNewValueAndKeys(RefCountedCache.scala:31) [spark-cassandra-connector_2.10-1.4.1.jar:1.4.1]
at com.datastax.spark.connector.cql.RefCountedCache.acquire(RefCountedCache.scala:56) [spark-cassandra-connector_2.10-1.4.1.jar:1.4.1]
at com.datastax.spark.connector.cql.CassandraConnector.openSession(CassandraConnector.scala:81) [spark-cassandra-connector_2.10-1.4.1.jar:1.4.1]
at com.datastax.spark.connector.cql.CassandraConnector.withSessionDo(CassandraConnector.scala:109) [spark-cassandra-connector_2.10-1.4.1.jar:1.4.1]
at com.datastax.spark.connector.cql.CassandraConnector.withClusterDo(CassandraConnector.scala:120) [spark-cassandra-connector_2.10-1.4.1.jar:1.4.1]
at com.datastax.spark.connector.cql.Schema$.fromCassandra(Schema.scala:241) [spark-cassandra-connector_2.10-1.4.1.jar:1.4.1]
at com.datastax.spark.connector.rdd.CassandraTableRowReaderProvider$class.tableDef(CassandraTableRowReaderProvider.scala:51) [spark-cassandra-connector_2.10-1.4.1.jar:1.4.1]
at com.datastax.spark.connector.rdd.CassandraTableScanRDD.tableDef$lzycompute(CassandraTableScanRDD.scala:59) [spark-cassandra-connector_2.10-1.4.1.jar:1.4.1]
at com.datastax.spark.connector.rdd.CassandraTableScanRDD.tableDef(CassandraTableScanRDD.scala:59) [spark-cassandra-connector_2.10-1.4.1.jar:1.4.1]
at com.datastax.spark.connector.rdd.CassandraTableRowReaderProvider$class.verify(CassandraTableRowReaderProvider.scala:150) [spark-cassandra-connector_2.10-1.4.1.jar:1.4.1]
at com.datastax.spark.connector.rdd.CassandraTableScanRDD.verify(CassandraTableScanRDD.scala:59) [spark-cassandra-connector_2.10-1.4.1.jar:1.4.1]
at com.datastax.spark.connector.rdd.CassandraTableScanRDD.getPartitions(CassandraTableScanRDD.scala:143) [spark-cassandra-connector_2.10-1.4.1.jar:1.4.1]
at org.apache.spark.rdd.RDD$$anonfun$partitions$2.apply(RDD.scala:219) [spark-core_2.10-1.4.2.2.jar:1.4.2.2]
at org.apache.spark.rdd.RDD$$anonfun$partitions$2.apply(RDD.scala:217) [spark-core_2.10-1.4.2.2.jar:1.4.2.2]
at scala.Option.getOrElse(Option.scala:120) [scala-library-2.10.5.jar:na]
at org.apache.spark.rdd.RDD.partitions(RDD.scala:217) [spark-core_2.10-1.4.2.2.jar:1.4.2.2]
at org.apache.spark.rdd.MapPartitionsRDD.getPartitions(MapPartitionsRDD.scala:32) [spark-core_2.10-1.4.2.2.jar:1.4.2.2]
at org.apache.spark.rdd.RDD$$anonfun$partitions$2.apply(RDD.scala:219) [spark-core_2.10-1.4.2.2.jar:1.4.2.2]
at org.apache.spark.rdd.RDD$$anonfun$partitions$2.apply(RDD.scala:217) [spark-core_2.10-1.4.2.2.jar:1.4.2.2]
at scala.Option.getOrElse(Option.scala:120) [scala-library-2.10.5.jar:na]
at org.apache.spark.rdd.RDD.partitions(RDD.scala:217) [spark-core_2.10-1.4.2.2.jar:1.4.2.2]
at org.apache.spark.rdd.MapPartitionsRDD.getPartitions(MapPartitionsRDD.scala:32) [spark-core_2.10-1.4.2.2.jar:1.4.2.2]
at org.apache.spark.rdd.RDD$$anonfun$partitions$2.apply(RDD.scala:219) [spark-core_2.10-1.4.2.2.jar:1.4.2.2]
at org.apache.spark.rdd.RDD$$anonfun$partitions$2.apply(RDD.scala:217) [spark-core_2.10-1.4.2.2.jar:1.4.2.2]
at scala.Option.getOrElse(Option.scala:120) [scala-library-2.10.5.jar:na]
at org.apache.spark.rdd.RDD.partitions(RDD.scala:217) [spark-core_2.10-1.4.2.2.jar:1.4.2.2]
at org.apache.spark.rdd.MapPartitionsRDD.getPartitions(MapPartitionsRDD.scala:32) [spark-core_2.10-1.4.2.2.jar:1.4.2.2]
at org.apache.spark.rdd.RDD$$anonfun$partitions$2.apply(RDD.scala:219) [spark-core_2.10-1.4.2.2.jar:1.4.2.2]
at org.apache.spark.rdd.RDD$$anonfun$partitions$2.apply(RDD.scala:217) [spark-core_2.10-1.4.2.2.jar:1.4.2.2]
at scala.Option.getOrElse(Option.scala:120) [scala-library-2.10.5.jar:na]
at org.apache.spark.rdd.RDD.partitions(RDD.scala:217) [spark-core_2.10-1.4.2.2.jar:1.4.2.2]
at org.apache.spark.SparkContext.runJob(SparkContext.scala:1806) [spark-core_2.10-1.4.2.2.jar:1.4.2.2]
at org.apache.spark.rdd.RDD.count(RDD.scala:1099) [spark-core_2.10-1.4.2.2.jar:1.4.2.2]
at com.treefin.stats.UserStatistics$.main(UserStatistics.scala:24) [stats_2.10-1.0.jar:1.0]
at com.treefin.stats.UserStatistics.main(UserStatistics.scala) [stats_2.10-1.0.jar:1.0]
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_65]
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) ~[na:1.8.0_65]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) ~[na:1.8.0_65]
at java.lang.reflect.Method.invoke(Unknown Source) ~[na:1.8.0_65]
at org.apache.spark.deploy.SparkSubmit$.org$apache$spark$deploy$SparkSubmit$$runMain(SparkSubmit.scala:665) [spark-core_2.10-1.4.2.2.jar:4.8.4]
at org.apache.spark.deploy.SparkSubmit$.doRunMain$1(SparkSubmit.scala:170) [spark-core_2.10-1.4.2.2.jar:4.8.4]
at org.apache.spark.deploy.SparkSubmit$.submit(SparkSubmit.scala:193) [spark-core_2.10-1.4.2.2.jar:4.8.4]
at org.apache.spark.deploy.SparkSubmit$.main(SparkSubmit.scala:112) [spark-core_2.10-1.4.2.2.jar:4.8.4]
at org.apache.spark.deploy.DseSparkSubmitBootstrapper$.main(DseSparkSubmitBootstrapper.scala:45) [dse-spark-4.8.4.jar:4.8.4]
at org.apache.spark.deploy.DseSparkSubmitBootstrapper.main(DseSparkSubmitBootstrapper.scala) [dse-spark-4.8.4.jar:4.8.4]

我们的系统在使用 GLIBC_2.12 的 CentOS 6.5 上运行。不过它仍然应该得到支持：http://www.datastax.com/products/datastax-enterprise#DSE-Supported-Platforms-Table

有什么办法可以解决这个问题并重新使用 epoll 吗？谢谢！

Answer 1

可以在此处找到本机传输的文档： https://github.com/netty/netty/wiki/Native-transports

在 CentOS 中，您可以使用原生 Linux 驱动程序。

要在 Maven 中做到这一点，您可以像这样添加一些依赖项：

<dependency>
    <groupId>io.netty</groupId>
    <artifactId>netty-transport-native-epoll</artifactId>
    <version>4.0.27.Final</version>
    <classifier>linux-x86_64</classifier>
  </dependency>

我看到您正在使用 Scala。我对 sbt 的了解非常有限，但根据文档，将其添加到 libraryDependencies 应该可以工作（如果 "${project.version}" 不起作用，请使用像 4.0.27.Final 这样的硬编码值）：

"io.netty" % "netty-transport-native-epoll" % "${project.version}" classifier "linux-x86_64"

this related answer 也可能有用。

正如您所指出的，-Dcom.datastax.driver.FORCE_NIO=true 会抑制警告，如果您不在 Linux 上，这是一个选项。