/*
* 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.storage
import java.io.{IOException, File, FileOutputStream, RandomAccessFile}
import java.nio.ByteBuffer
import java.nio.channels.FileChannel.MapMode
import org.apache.spark.Logging
import org.apache.spark.serializer.Serializer
import org.apache.spark.util.Utils
/**
* Stores BlockManager blocks on disk.
*/
private[spark] class DiskStore(blockManager: BlockManager, diskManager: DiskBlockManager)
extends BlockStore(blockManager) with Logging {
val minMemoryMapBytes = blockManager.conf.getLong("spark.storage.memoryMapThreshold", 2 * 4096L)
override def getSize(blockId: BlockId): Long = {
diskManager.getFile(blockId.name).length
}
override def putBytes(blockId: BlockId, _bytes: ByteBuffer, level: StorageLevel): PutResult = {
// So that we do not modify the input offsets !
// duplicate does not copy buffer, so inexpensive
val bytes = _bytes.duplicate()
logDebug(s"Attempting to put block $blockId")
val startTime = System.currentTimeMillis
val file = diskManager.getFile(blockId)
val channel = new FileOutputStream(file).getChannel
while (bytes.remaining > 0) {
channel.write(bytes)
}
channel.close()
val finishTime = System.currentTimeMillis
logDebug("Block %s stored as %s file on disk in %d ms".format(
file.getName, Utils.bytesToString(bytes.limit), finishTime - startTime))
PutResult(bytes.limit(), Right(bytes.duplicate()))
}
override def putArray(
blockId: BlockId,
values: Array[Any],
level: StorageLevel,
returnValues: Boolean): PutResult = {
putIterator(blockId, values.toIterator, level, returnValues)
}
override def putIterator(
blockId: BlockId,
values: Iterator[Any],
level: StorageLevel,
returnValues: Boolean): PutResult = {
logDebug(s"Attempting to write values for block $blockId")
val startTime = System.currentTimeMillis
val file = diskManager.getFile(blockId)
val outputStream = new FileOutputStream(file)
try {
try {
blockManager.dataSerializeStream(blockId, outputStream, values)
} finally {
// Close outputStream here because it should be closed before file is deleted.
outputStream.close()
}
} catch {
case e: Throwable =>
if (file.exists()) {
file.delete()
}
throw e
}
val length = file.length
val timeTaken = System.currentTimeMillis - startTime
logDebug("Block %s stored as %s file on disk in %d ms".format(
file.getName, Utils.bytesToString(length), timeTaken))
if (returnValues) {
// Return a byte buffer for the contents of the file
val buffer = getBytes(blockId).get
PutResult(length, Right(buffer))
} else {
PutResult(length, null)
}
}
private def getBytes(file: File, offset: Long, length: Long): Option[ByteBuffer] = {
val channel = new RandomAccessFile(file, "r").getChannel
try {
// For small files, directly read rather than memory map
if (length < minMemoryMapBytes) {
val buf = ByteBuffer.allocate(length.toInt)
channel.position(offset)
while (buf.remaining() != 0) {
if (channel.read(buf) == -1) {
throw new IOException("Reached EOF before filling buffer\n" +
s"offset=$offset\nfile=${file.getAbsolutePath}\nbuf.remaining=${buf.remaining}")
}
}
buf.flip()
Some(buf)
} else {
Some(channel.map(MapMode.READ_ONLY, offset, length))
}
} finally {
channel.close()
}
}
override def getBytes(blockId: BlockId): Option[ByteBuffer] = {
val file = diskManager.getFile(blockId.name)
getBytes(file, 0, file.length)
}
def getBytes(segment: FileSegment): Option[ByteBuffer] = {
getBytes(segment.file, segment.offset, segment.length)
}
override def getValues(blockId: BlockId): Option[Iterator[Any]] = {
getBytes(blockId).map(buffer => blockManager.dataDeserialize(blockId, buffer))
}
/**
* A version of getValues that allows a custom serializer. This is used as part of the
* shuffle short-circuit code.
*/
def getValues(blockId: BlockId, serializer: Serializer): Option[Iterator[Any]] = {
// TODO: Should bypass getBytes and use a stream based implementation, so that
// we won't use a lot of memory during e.g. external sort merge.
getBytes(blockId).map(bytes => blockManager.dataDeserialize(blockId, bytes, serializer))
}
override def remove(blockId: BlockId): Boolean = {
val file = diskManager.getFile(blockId.name)
// If consolidation mode is used With HashShuffleMananger, the physical filename for the block
// is different from blockId.name. So the file returns here will not be exist, thus we avoid to
// delete the whole consolidated file by mistake.
if (file.exists()) {
file.delete()
} else {
false
}
}
override def contains(blockId: BlockId): Boolean = {
val file = diskManager.getFile(blockId.name)
file.exists()
}
}