Many resources are needed to download a project. Please understand that we have to compensate our server costs. Thank you in advance. Project price only 1 $
You can buy this project and download/modify it how often you want.
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.spark.serializer
import java.io.{EOFException, IOException, InputStream, OutputStream}
import java.nio.ByteBuffer
import javax.annotation.Nullable
import scala.reflect.ClassTag
import com.esotericsoftware.kryo.{Kryo, KryoException}
import com.esotericsoftware.kryo.io.{Input => KryoInput, Output => KryoOutput}
import com.esotericsoftware.kryo.serializers.{JavaSerializer => KryoJavaSerializer}
import com.twitter.chill.{AllScalaRegistrar, EmptyScalaKryoInstantiator}
import org.apache.avro.generic.{GenericData, GenericRecord}
import org.roaringbitmap.{ArrayContainer, BitmapContainer, RoaringArray, RoaringBitmap}
import org.apache.spark._
import org.apache.spark.api.python.PythonBroadcast
import org.apache.spark.broadcast.HttpBroadcast
import org.apache.spark.network.nio.{GetBlock, GotBlock, PutBlock}
import org.apache.spark.network.util.ByteUnit
import org.apache.spark.scheduler.{CompressedMapStatus, HighlyCompressedMapStatus}
import org.apache.spark.storage._
import org.apache.spark.util.{BoundedPriorityQueue, SerializableConfiguration, SerializableJobConf}
import org.apache.spark.util.collection.CompactBuffer
/**
* A Spark serializer that uses the [[https://code.google.com/p/kryo/ Kryo serialization library]].
*
* Note that this serializer is not guaranteed to be wire-compatible across different versions of
* Spark. It is intended to be used to serialize/de-serialize data within a single
* Spark application.
*/
class KryoSerializer(conf: SparkConf)
extends org.apache.spark.serializer.Serializer
with Logging
with Serializable {
private val bufferSizeKb = conf.getSizeAsKb("spark.kryoserializer.buffer", "64k")
if (bufferSizeKb >= ByteUnit.GiB.toKiB(2)) {
throw new IllegalArgumentException("spark.kryoserializer.buffer must be less than " +
s"2048 mb, got: + ${ByteUnit.KiB.toMiB(bufferSizeKb)} mb.")
}
private val bufferSize = ByteUnit.KiB.toBytes(bufferSizeKb).toInt
val maxBufferSizeMb = conf.getSizeAsMb("spark.kryoserializer.buffer.max", "64m").toInt
if (maxBufferSizeMb >= ByteUnit.GiB.toMiB(2)) {
throw new IllegalArgumentException("spark.kryoserializer.buffer.max must be less than " +
s"2048 mb, got: + $maxBufferSizeMb mb.")
}
private val maxBufferSize = ByteUnit.MiB.toBytes(maxBufferSizeMb).toInt
private val referenceTracking = conf.getBoolean("spark.kryo.referenceTracking", true)
private val registrationRequired = conf.getBoolean("spark.kryo.registrationRequired", false)
private val userRegistrator = conf.getOption("spark.kryo.registrator")
private val classesToRegister = conf.get("spark.kryo.classesToRegister", "")
.split(',')
.filter(!_.isEmpty)
private val avroSchemas = conf.getAvroSchema
def newKryoOutput(): KryoOutput = new KryoOutput(bufferSize, math.max(bufferSize, maxBufferSize))
def newKryo(): Kryo = {
val instantiator = new EmptyScalaKryoInstantiator
val kryo = instantiator.newKryo()
kryo.setRegistrationRequired(registrationRequired)
val oldClassLoader = Thread.currentThread.getContextClassLoader
val classLoader = defaultClassLoader.getOrElse(Thread.currentThread.getContextClassLoader)
// Allow disabling Kryo reference tracking if user knows their object graphs don't have loops.
// Do this before we invoke the user registrator so the user registrator can override this.
kryo.setReferences(referenceTracking)
for (cls <- KryoSerializer.toRegister) {
kryo.register(cls)
}
// For results returned by asJavaIterable. See JavaIterableWrapperSerializer.
kryo.register(JavaIterableWrapperSerializer.wrapperClass, new JavaIterableWrapperSerializer)
// Allow sending classes with custom Java serializers
kryo.register(classOf[SerializableWritable[_]], new KryoJavaSerializer())
kryo.register(classOf[SerializableConfiguration], new KryoJavaSerializer())
kryo.register(classOf[SerializableJobConf], new KryoJavaSerializer())
kryo.register(classOf[HttpBroadcast[_]], new KryoJavaSerializer())
kryo.register(classOf[PythonBroadcast], new KryoJavaSerializer())
kryo.register(classOf[GenericRecord], new GenericAvroSerializer(avroSchemas))
kryo.register(classOf[GenericData.Record], new GenericAvroSerializer(avroSchemas))
try {
// scalastyle:off classforname
// Use the default classloader when calling the user registrator.
Thread.currentThread.setContextClassLoader(classLoader)
// Register classes given through spark.kryo.classesToRegister.
classesToRegister
.foreach { className => kryo.register(Class.forName(className, true, classLoader)) }
// Allow the user to register their own classes by setting spark.kryo.registrator.
userRegistrator
.map(Class.forName(_, true, classLoader).newInstance().asInstanceOf[KryoRegistrator])
.foreach { reg => reg.registerClasses(kryo) }
// scalastyle:on classforname
} catch {
case e: Exception =>
throw new SparkException(s"Failed to register classes with Kryo", e)
} finally {
Thread.currentThread.setContextClassLoader(oldClassLoader)
}
// Register Chill's classes; we do this after our ranges and the user's own classes to let
// our code override the generic serializers in Chill for things like Seq
new AllScalaRegistrar().apply(kryo)
kryo.setClassLoader(classLoader)
kryo
}
override def newInstance(): SerializerInstance = {
new KryoSerializerInstance(this)
}
private[spark] override lazy val supportsRelocationOfSerializedObjects: Boolean = {
// If auto-reset is disabled, then Kryo may store references to duplicate occurrences of objects
// in the stream rather than writing those objects' serialized bytes, breaking relocation. See
// https://groups.google.com/d/msg/kryo-users/6ZUSyfjjtdo/FhGG1KHDXPgJ for more details.
newInstance().asInstanceOf[KryoSerializerInstance].getAutoReset()
}
}
private[spark]
class KryoSerializationStream(
serInstance: KryoSerializerInstance,
outStream: OutputStream) extends SerializationStream {
private[this] var output: KryoOutput = new KryoOutput(outStream)
private[this] var kryo: Kryo = serInstance.borrowKryo()
override def writeObject[T: ClassTag](t: T): SerializationStream = {
kryo.writeClassAndObject(output, t)
this
}
override def flush() {
if (output == null) {
throw new IOException("Stream is closed")
}
output.flush()
}
override def close() {
if (output != null) {
try {
output.close()
} finally {
serInstance.releaseKryo(kryo)
kryo = null
output = null
}
}
}
}
private[spark]
class KryoDeserializationStream(
serInstance: KryoSerializerInstance,
inStream: InputStream) extends DeserializationStream {
private[this] var input: KryoInput = new KryoInput(inStream)
private[this] var kryo: Kryo = serInstance.borrowKryo()
override def readObject[T: ClassTag](): T = {
try {
kryo.readClassAndObject(input).asInstanceOf[T]
} catch {
// DeserializationStream uses the EOF exception to indicate stopping condition.
case e: KryoException if e.getMessage.toLowerCase.contains("buffer underflow") =>
throw new EOFException
}
}
override def close() {
if (input != null) {
try {
// Kryo's Input automatically closes the input stream it is using.
input.close()
} finally {
serInstance.releaseKryo(kryo)
kryo = null
input = null
}
}
}
}
private[spark] class KryoSerializerInstance(ks: KryoSerializer) extends SerializerInstance {
/**
* A re-used [[Kryo]] instance. Methods will borrow this instance by calling `borrowKryo()`, do
* their work, then release the instance by calling `releaseKryo()`. Logically, this is a caching
* pool of size one. SerializerInstances are not thread-safe, hence accesses to this field are
* not synchronized.
*/
@Nullable private[this] var cachedKryo: Kryo = borrowKryo()
/**
* Borrows a [[Kryo]] instance. If possible, this tries to re-use a cached Kryo instance;
* otherwise, it allocates a new instance.
*/
private[serializer] def borrowKryo(): Kryo = {
if (cachedKryo != null) {
val kryo = cachedKryo
// As a defensive measure, call reset() to clear any Kryo state that might have been modified
// by the last operation to borrow this instance (see SPARK-7766 for discussion of this issue)
kryo.reset()
cachedKryo = null
kryo
} else {
ks.newKryo()
}
}
/**
* Release a borrowed [[Kryo]] instance. If this serializer instance already has a cached Kryo
* instance, then the given Kryo instance is discarded; otherwise, the Kryo is stored for later
* re-use.
*/
private[serializer] def releaseKryo(kryo: Kryo): Unit = {
if (cachedKryo == null) {
cachedKryo = kryo
}
}
// Make these lazy vals to avoid creating a buffer unless we use them.
private lazy val output = ks.newKryoOutput()
private lazy val input = new KryoInput()
override def serialize[T: ClassTag](t: T): ByteBuffer = {
output.clear()
val kryo = borrowKryo()
try {
kryo.writeClassAndObject(output, t)
} catch {
case e: KryoException if e.getMessage.startsWith("Buffer overflow") =>
throw new SparkException(s"Kryo serialization failed: ${e.getMessage}. To avoid this, " +
"increase spark.kryoserializer.buffer.max value.")
} finally {
releaseKryo(kryo)
}
ByteBuffer.wrap(output.toBytes)
}
override def deserialize[T: ClassTag](bytes: ByteBuffer): T = {
val kryo = borrowKryo()
try {
input.setBuffer(bytes.array)
kryo.readClassAndObject(input).asInstanceOf[T]
} finally {
releaseKryo(kryo)
}
}
override def deserialize[T: ClassTag](bytes: ByteBuffer, loader: ClassLoader): T = {
val kryo = borrowKryo()
val oldClassLoader = kryo.getClassLoader
try {
kryo.setClassLoader(loader)
input.setBuffer(bytes.array)
kryo.readClassAndObject(input).asInstanceOf[T]
} finally {
kryo.setClassLoader(oldClassLoader)
releaseKryo(kryo)
}
}
override def serializeStream(s: OutputStream): SerializationStream = {
new KryoSerializationStream(this, s)
}
override def deserializeStream(s: InputStream): DeserializationStream = {
new KryoDeserializationStream(this, s)
}
/**
* Returns true if auto-reset is on. The only reason this would be false is if the user-supplied
* registrator explicitly turns auto-reset off.
*/
def getAutoReset(): Boolean = {
val field = classOf[Kryo].getDeclaredField("autoReset")
field.setAccessible(true)
val kryo = borrowKryo()
try {
field.get(kryo).asInstanceOf[Boolean]
} finally {
releaseKryo(kryo)
}
}
}
/**
* Interface implemented by clients to register their classes with Kryo when using Kryo
* serialization.
*/
trait KryoRegistrator {
def registerClasses(kryo: Kryo)
}
private[serializer] object KryoSerializer {
// Commonly used classes.
private val toRegister: Seq[Class[_]] = Seq(
ByteBuffer.allocate(1).getClass,
classOf[StorageLevel],
classOf[PutBlock],
classOf[GotBlock],
classOf[GetBlock],
classOf[CompressedMapStatus],
classOf[HighlyCompressedMapStatus],
classOf[RoaringBitmap],
classOf[RoaringArray],
classOf[RoaringArray.Element],
classOf[Array[RoaringArray.Element]],
classOf[ArrayContainer],
classOf[BitmapContainer],
classOf[CompactBuffer[_]],
classOf[BlockManagerId],
classOf[Array[Byte]],
classOf[Array[Short]],
classOf[Array[Long]],
classOf[BoundedPriorityQueue[_]],
classOf[SparkConf]
)
}
/**
* A Kryo serializer for serializing results returned by asJavaIterable.
*
* The underlying object is scala.collection.convert.Wrappers$IterableWrapper.
* Kryo deserializes this into an AbstractCollection, which unfortunately doesn't work.
*/
private class JavaIterableWrapperSerializer
extends com.esotericsoftware.kryo.Serializer[java.lang.Iterable[_]] {
import JavaIterableWrapperSerializer._
override def write(kryo: Kryo, out: KryoOutput, obj: java.lang.Iterable[_]): Unit = {
// If the object is the wrapper, simply serialize the underlying Scala Iterable object.
// Otherwise, serialize the object itself.
if (obj.getClass == wrapperClass && underlyingMethodOpt.isDefined) {
kryo.writeClassAndObject(out, underlyingMethodOpt.get.invoke(obj))
} else {
kryo.writeClassAndObject(out, obj)
}
}
override def read(kryo: Kryo, in: KryoInput, clz: Class[java.lang.Iterable[_]])
: java.lang.Iterable[_] = {
kryo.readClassAndObject(in) match {
case scalaIterable: Iterable[_] =>
scala.collection.JavaConversions.asJavaIterable(scalaIterable)
case javaIterable: java.lang.Iterable[_] =>
javaIterable
}
}
}
private object JavaIterableWrapperSerializer extends Logging {
// The class returned by asJavaIterable (scala.collection.convert.Wrappers$IterableWrapper).
val wrapperClass =
scala.collection.convert.WrapAsJava.asJavaIterable(Seq(1)).getClass
// Get the underlying method so we can use it to get the Scala collection for serialization.
private val underlyingMethodOpt = {
try Some(wrapperClass.getDeclaredMethod("underlying")) catch {
case e: Exception =>
logError("Failed to find the underlying field in " + wrapperClass, e)
None
}
}
}
