John Brock created SPARK-21928: ---------------------------------- Summary: ML LogisticRegression training occasionally produces java.lang.ClassNotFoundException when attempting to load custom Kryo registrator class Key: SPARK-21928 URL: https://issues.apache.org/jira/browse/SPARK-21928 Project: Spark Issue Type: Bug Components: ML Affects Versions: 2.2.0 Reporter: John Brock
I unfortunately can't reliably reproduce this bug; it happens only occasionally, when training a logistic regression model with very large datasets. The training will often proceed through several {{treeAggregate}} calls without any problems, and then suddenly workers will start running into this {{java.lang.ClassNotFoundException}}. After doing some debugging, it seems that whenever this error happens, Spark is trying to use the {{sun.misc.Launcher$AppClassLoader}} {{ClassLoader}} instance instead of the usual {{org.apache.spark.util.MutableURLClassLoader}}. {{MutableURLClassLoader}} can see my custom Kryo registrator, but the {{AppClassLoader}} instance can't. When this error does pop up, it's usually accompanied by the task seeming to hang, and I need to kill Spark manually. I'm running a Spark application in cluster mode via spark-submit, and I have a custom Kryo registrator. The JAR is built with {{sbt assembly}}. Exception message: {noformat} 17/08/29 22:39:04 ERROR TransportRequestHandler: Error opening block StreamChunkId{streamId=542074019336, chunkIndex=0} for request from /10.0.29.65:34332 org.apache.spark.SparkException: Failed to register classes with Kryo at org.apache.spark.serializer.KryoSerializer.newKryo(KryoSerializer.scala:139) at org.apache.spark.serializer.KryoSerializerInstance.borrowKryo(KryoSerializer.scala:292) at org.apache.spark.serializer.KryoSerializerInstance.<init>(KryoSerializer.scala:277) at org.apache.spark.serializer.KryoSerializer.newInstance(KryoSerializer.scala:186) at org.apache.spark.serializer.SerializerManager.dataSerializeStream(SerializerManager.scala:169) at org.apache.spark.storage.BlockManager$$anonfun$dropFromMemory$3.apply(BlockManager.scala:1382) at org.apache.spark.storage.BlockManager$$anonfun$dropFromMemory$3.apply(BlockManager.scala:1377) at org.apache.spark.storage.DiskStore.put(DiskStore.scala:69) at org.apache.spark.storage.BlockManager.dropFromMemory(BlockManager.scala:1377) at org.apache.spark.storage.memory.MemoryStore.org$apache$spark$storage$memory$MemoryStore$$dropBlock$1(MemoryStore.scala:524) at org.apache.spark.storage.memory.MemoryStore$$anonfun$evictBlocksToFreeSpace$2.apply(MemoryStore.scala:545) at org.apache.spark.storage.memory.MemoryStore$$anonfun$evictBlocksToFreeSpace$2.apply(MemoryStore.scala:539) at scala.collection.mutable.ResizableArray$class.foreach(ResizableArray.scala:59) at scala.collection.mutable.ArrayBuffer.foreach(ArrayBuffer.scala:48) at org.apache.spark.storage.memory.MemoryStore.evictBlocksToFreeSpace(MemoryStore.scala:539) at org.apache.spark.memory.StorageMemoryPool.acquireMemory(StorageMemoryPool.scala:92) at org.apache.spark.memory.StorageMemoryPool.acquireMemory(StorageMemoryPool.scala:73) at org.apache.spark.memory.StaticMemoryManager.acquireStorageMemory(StaticMemoryManager.scala:72) at org.apache.spark.storage.memory.MemoryStore.putBytes(MemoryStore.scala:147) at org.apache.spark.storage.BlockManager.maybeCacheDiskBytesInMemory(BlockManager.scala:1143) at org.apache.spark.storage.BlockManager.org$apache$spark$storage$BlockManager$$doGetLocalBytes(BlockManager.scala:594) at org.apache.spark.storage.BlockManager$$anonfun$getLocalBytes$2.apply(BlockManager.scala:559) at org.apache.spark.storage.BlockManager$$anonfun$getLocalBytes$2.apply(BlockManager.scala:559) at scala.Option.map(Option.scala:146) at org.apache.spark.storage.BlockManager.getLocalBytes(BlockManager.scala:559) at org.apache.spark.storage.BlockManager.getBlockData(BlockManager.scala:353) at org.apache.spark.network.netty.NettyBlockRpcServer$$anonfun$1.apply(NettyBlockRpcServer.scala:61) at org.apache.spark.network.netty.NettyBlockRpcServer$$anonfun$1.apply(NettyBlockRpcServer.scala:60) at scala.collection.Iterator$$anon$11.next(Iterator.scala:409) at scala.collection.convert.Wrappers$IteratorWrapper.next(Wrappers.scala:31) at org.apache.spark.network.server.OneForOneStreamManager.getChunk(OneForOneStreamManager.java:89) at org.apache.spark.network.server.TransportRequestHandler.processFetchRequest(TransportRequestHandler.java:125) at org.apache.spark.network.server.TransportRequestHandler.handle(TransportRequestHandler.java:103) at org.apache.spark.network.server.TransportChannelHandler.channelRead(TransportChannelHandler.java:118) at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:357) at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:343) at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:336) at io.netty.handler.timeout.IdleStateHandler.channelRead(IdleStateHandler.java:287) at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:357) at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:343) at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:336) at io.netty.handler.codec.MessageToMessageDecoder.channelRead(MessageToMessageDecoder.java:102) at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:357) at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:343) at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:336) at org.apache.spark.network.util.TransportFrameDecoder.channelRead(TransportFrameDecoder.java:85) at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:357) at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:343) at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:336) at io.netty.channel.DefaultChannelPipeline$HeadContext.channelRead(DefaultChannelPipeline.java:1294) at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:357) at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:343) at io.netty.channel.DefaultChannelPipeline.fireChannelRead(DefaultChannelPipeline.java:911) at io.netty.channel.nio.AbstractNioByteChannel$NioByteUnsafe.read(AbstractNioByteChannel.java:131) at io.netty.channel.nio.NioEventLoop.processSelectedKey(NioEventLoop.java:643) at io.netty.channel.nio.NioEventLoop.processSelectedKeysOptimized(NioEventLoop.java:566) at io.netty.channel.nio.NioEventLoop.processSelectedKeys(NioEventLoop.java:480) at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:442) at io.netty.util.concurrent.SingleThreadEventExecutor$2.run(SingleThreadEventExecutor.java:131) at io.netty.util.concurrent.DefaultThreadFactory$DefaultRunnableDecorator.run(DefaultThreadFactory.java:144) at java.lang.Thread.run(Thread.java:745) Caused by: java.lang.ClassNotFoundException: com.foo.bar.MyKryoRegistrator at java.net.URLClassLoader.findClass(URLClassLoader.java:381) at java.lang.ClassLoader.loadClass(ClassLoader.java:424) at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:331) at java.lang.ClassLoader.loadClass(ClassLoader.java:357) at java.lang.Class.forName0(Native Method) at java.lang.Class.forName(Class.java:348) at org.apache.spark.serializer.KryoSerializer$$anonfun$newKryo$5.apply(KryoSerializer.scala:134) at org.apache.spark.serializer.KryoSerializer$$anonfun$newKryo$5.apply(KryoSerializer.scala:134) at scala.collection.TraversableLike$$anonfun$map$1.apply(TraversableLike.scala:234) at scala.collection.TraversableLike$$anonfun$map$1.apply(TraversableLike.scala:234) at scala.collection.IndexedSeqOptimized$class.foreach(IndexedSeqOptimized.scala:33) at scala.collection.mutable.ArrayOps$ofRef.foreach(ArrayOps.scala:186) at scala.collection.TraversableLike$class.map(TraversableLike.scala:234) at scala.collection.mutable.ArrayOps$ofRef.map(ArrayOps.scala:186) at org.apache.spark.serializer.KryoSerializer.newKryo(KryoSerializer.scala:134) ... 60 more {noformat} My Spark session is created like so: {code:java} val spark = SparkSession.builder() .appName("FooBar") .config("spark.serializer", "org.apache.spark.serializer.KryoSerializer") .config("spark.kryoserializer.buffer.max", "2047m") .config("spark.kryo.registrator","com.foo.bar.MyKryoRegistrator") .config("spark.kryo.registrationRequired", "true") .config("spark.network.timeout", "3600s") .config("spark.driver.maxResultSize", "0") .config("spark.rdd.compress", "true") .config("spark.shuffle.spill", "true") .getOrCreate() {code} Here are the config options I'm passing to spark-submit: {noformat} --conf "spark.executor.heartbeatInterval=400s" --conf "spark.speculation=true" --conf "spark.speculation.multiplier=30" --conf "spark.speculation.quantile=0.95" --conf "spark.memory.useLegacyMode=true" --conf "spark.shuffle.memoryFraction=0.8" --conf "spark.storage.memoryFraction=0.2" --driver-java-options "-XX:+UseG1GC" {noformat} I was able to find a workaround: copy your application JAR to each of the machines in your cluster, and pass the JAR's path to {{spark-submit}} with: {noformat} --conf "spark.driver.extraClassPath=/path/to/sparklogisticregression.jar" --conf "spark.executor.extraClassPath=/path/to/sparklogisticregression.jar" {noformat} -- This message was sent by Atlassian JIRA (v6.4.14#64029) --------------------------------------------------------------------- To unsubscribe, e-mail: issues-unsubscr...@spark.apache.org For additional commands, e-mail: issues-h...@spark.apache.org