Question

我正在尝试充分利用kryo序列化来获得火花。设置

.set("spark.kryo.registrationRequired", "true")

这将让我知道需要注册哪些类。我已经注册了大约40个课程，我的一些课程和一些火花课程。我跟着Require kryo serialization in Spark (Scala)帖子注册/设置了一切。

我现在遇到以下内容，无法弄清楚如何在scala中注册它。有人解决了这个问题吗？

我尝试了很多不同的组合，包括：

kryo.register(classOf[Array[Array[Byte]]])
conf.set("classesToRegister", "classOf[Array[Array[Byte]]]")
conf.registerKryoClasses(Array(classOf[Array[Array[Byte]]]))

我发现了一条未答复的帖子https://mail-archives.apache.org/mod_mbox/spark-user/201603.mbox/%3CCAHCfvsSyUpx78ZFS_A9ycxvtO1=Jp7DfCCAeJKHyHZ1sugqHEQ@mail.gmail.com%3E，说明了同样的问题。

java.lang.RuntimeException: com.esotericsoftware.kryo.KryoException: java.lang.IllegalArgumentException: Class is not registered: byte[][]
Note: To register this class use: kryo.register(byte[][].class);
Serialization trace:
buffers (org.apache.spark.sql.columnar.CachedBatch)
at com.esotericsoftware.kryo.serializers.FieldSerializer$ObjectField.write(FieldSerializer.java:585)
at com.esotericsoftware.kryo.serializers.FieldSerializer.write(FieldSerializer.java:213)
at com.esotericsoftware.kryo.Kryo.writeClassAndObject(Kryo.java:568)
at org.apache.spark.serializer.KryoSerializationStream.writeObject(KryoSerializer.scala:158)
at org.apache.spark.serializer.SerializationStream.writeAll(Serializer.scala:153)
at org.apache.spark.storage.BlockManager.dataSerializeStream(BlockManager.scala:1190)
at org.apache.spark.storage.BlockManager.dataSerialize(BlockManager.scala:1199)
at org.apache.spark.storage.MemoryStore.getBytes(MemoryStore.scala:191)
at org.apache.spark.storage.BlockManager.doGetLocal(BlockManager.scala:480)
at org.apache.spark.storage.BlockManager.getBlockData(BlockManager.scala:302)
at org.apache.spark.network.netty.NettyBlockRpcServer$$anonfun$2.apply(NettyBlockRpcServer.scala:57)
at org.apache.spark.network.netty.NettyBlockRpcServer$$anonfun$2.apply(NettyBlockRpcServer.scala:57)
at scala.collection.TraversableLike$$anonfun$map$1.apply(TraversableLike.scala:244)
at scala.collection.TraversableLike$$anonfun$map$1.apply(TraversableLike.scala:244)
at scala.collection.IndexedSeqOptimized$class.foreach(IndexedSeqOptimized.scala:33)
at scala.collection.mutable.ArrayOps$ofRef.foreach(ArrayOps.scala:108)
at scala.collection.TraversableLike$class.map(TraversableLike.scala:244)
at scala.collection.mutable.ArrayOps$ofRef.map(ArrayOps.scala:108)
at org.apache.spark.network.netty.NettyBlockRpcServer.receive(NettyBlockRpcServer.scala:57)
at org.apache.spark.network.server.TransportRequestHandler.processRpcRequest(TransportRequestHandler.java:114)
at org.apache.spark.network.server.TransportRequestHandler.handle(TransportRequestHandler.java:87)
at org.apache.spark.network.server.TransportChannelHandler.channelRead0(TransportChannelHandler.java:101)
at org.apache.spark.network.server.TransportChannelHandler.channelRead0(TransportChannelHandler.java:51)
at io.netty.channel.SimpleChannelInboundHandler.channelRead(SimpleChannelInboundHandler.java:105)
at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:308)
at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:294)
at io.netty.handler.timeout.IdleStateHandler.channelRead(IdleStateHandler.java:266)
at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:308)
at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:294)
at io.netty.handler.codec.MessageToMessageDecoder.channelRead(MessageToMessageDecoder.java:103)
at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:308)
at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:294)
at io.netty.handler.codec.ByteToMessageDecoder.channelRead(ByteToMessageDecoder.java:244)
at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:308)
at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:294)
at io.netty.channel.DefaultChannelPipeline.fireChannelRead(DefaultChannelPipeline.java:846)
at io.netty.channel.nio.AbstractNioByteChannel$NioByteUnsafe.read(AbstractNioByteChannel.java:131)
at io.netty.channel.nio.NioEventLoop.processSelectedKey(NioEventLoop.java:511)
at io.netty.channel.nio.NioEventLoop.processSelectedKeysOptimized(NioEventLoop.java:468)
at io.netty.channel.nio.NioEventLoop.processSelectedKeys(NioEventLoop.java:382)
at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:354)
at io.netty.util.concurrent.SingleThreadEventExecutor$2.run(SingleThreadEventExecutor.java:111)
at java.lang.Thread.run(Thread.java:745)

Answer 1

conf.registerKryoClasses(Array( Class.forName("[[B")))

应该有效

Answer 2

我知道这个非常老的问题，但对于那些可能会为任何类的数组寻求解决方案的人来说：

case class Person(name: String)

conf.registerKryoClasses(Array(
   classOf[Array[Array[Person]]]
))

或者在这个特定问题的情况下：

conf.registerKryoClasses(Array(
   classOf[Array[Array[Byte]]]
))

如何使用kryo序列化为spark注册byte [] []

2 个答案: