org.apache.flink.runtime.operators.hash

Class HashPartition<BT,PT>

java.lang.Object

org.apache.flink.runtime.memory.AbstractPagedInputView

org.apache.flink.runtime.operators.hash.HashPartition<BT,PT>

Type Parameters:

BT - The type of the build side records.

PT - The type of the probe side records.

All Implemented Interfaces:

DataInput, DataInputView, SeekableDataInputView

Direct Known Subclasses:

ReOpenableHashPartition

public class HashPartition<BT,PT>
extends AbstractPagedInputView
implements SeekableDataInputView

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
protected static class	HashPartition.BuildSideBuffer

Field Summary

Fields

Modifier and Type	Field and Description
protected boolean	furtherPartitioning
protected int	nextOverflowBucket
protected int	numOverflowSegments
protected MemorySegment[]	overflowSegments
protected MemorySegment[]	partitionBuffers
protected ChannelWriterOutputView	probeSideBuffer
protected BlockChannelWriter<MemorySegment>	probeSideChannel
protected long	probeSideRecordCounter
protected int	recursionLevel

Fields inherited from class org.apache.flink.runtime.memory.AbstractPagedInputView

headerLength

Method Summary

Modifier and Type	Method and Description
void	clearAllMemory(List<MemorySegment> target)
void	finalizeBuildPhase(IOManager ioAccess, FileIOChannel.Enumerator probeChannelEnumerator, LinkedBlockingQueue<MemorySegment> bufferReturnQueue)
int	finalizeProbePhase(List<MemorySegment> freeMemory, List<HashPartition<BT,PT>> spilledPartitions, boolean keepUnprobedSpilledPartitions)
int	getBuildSideBlockCount()
BlockChannelWriter<MemorySegment>	getBuildSideChannel()
long	getBuildSideRecordCount()
protected int	getLimitForSegment(MemorySegment segment) Gets the limit for reading bytes from the given memory segment.
int	getNumOccupiedMemorySegments() Gets the number of memory segments used by this partition, which includes build side memory buffers and overflow memory segments.
int	getPartitionNumber() Gets the partition number of this partition.
int	getProbeSideBlockCount()
BlockChannelWriter<MemorySegment>	getProbeSideChannel()
long	getProbeSideRecordCount()
int	getRecursionLevel() Gets this partition's recursion level.
long	insertIntoBuildBuffer(BT record) Inserts the given object into the current buffer.
void	insertIntoProbeBuffer(PT record) Inserts the given record into the probe side buffers.
boolean	isInMemory() Checks whether this partition is in memory or spilled.
protected MemorySegment	nextSegment(MemorySegment current) The method by which concrete subclasses realize page crossing.
void	prepareProbePhase(IOManager ioAccess, FileIOChannel.Enumerator probeChannelEnumerator, LinkedBlockingQueue<MemorySegment> bufferReturnQueue)
protected void	setFurtherPatitioning(boolean v)
void	setReadPosition(long pointer) Sets the read pointer to the given position.
int	spillPartition(List<MemorySegment> target, IOManager ioAccess, FileIOChannel.ID targetChannel, LinkedBlockingQueue<MemorySegment> bufferReturnQueue) Spills this partition to disk and sets it up such that it continues spilling records that are added to it.

Methods inherited from class org.apache.flink.runtime.memory.AbstractPagedInputView

advance, clear, doAdvance, getCurrentPositionInSegment, getCurrentSegment, getCurrentSegmentLimit, getHeaderLength, read, read, readBoolean, readByte, readChar, readDouble, readFloat, readFully, readFully, readInt, readLine, readLong, readShort, readUnsignedByte, readUnsignedShort, readUTF, seekInput, skipBytes, skipBytesToRead

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface org.apache.flink.core.memory.DataInputView

read, read, skipBytesToRead

Methods inherited from interface java.io.DataInput

readBoolean, readByte, readChar, readDouble, readFloat, readFully, readFully, readInt, readLine, readLong, readShort, readUnsignedByte, readUnsignedShort, readUTF, skipBytes

Field Detail

overflowSegments

protected MemorySegment[] overflowSegments

numOverflowSegments

protected int numOverflowSegments

nextOverflowBucket

protected int nextOverflowBucket

partitionBuffers

protected MemorySegment[] partitionBuffers

probeSideBuffer

protected ChannelWriterOutputView probeSideBuffer

probeSideRecordCounter

protected long probeSideRecordCounter

recursionLevel

protected int recursionLevel

probeSideChannel

protected BlockChannelWriter<MemorySegment> probeSideChannel

furtherPartitioning

protected boolean furtherPartitioning

Method Detail

setFurtherPatitioning

protected void setFurtherPatitioning(boolean v)

getPartitionNumber

public int getPartitionNumber()

Gets the partition number of this partition.

Returns:

This partition's number.

getRecursionLevel

public int getRecursionLevel()

Gets this partition's recursion level.

Returns:

The partition's recursion level.

isInMemory

public final boolean isInMemory()

Checks whether this partition is in memory or spilled.

Returns:

True, if the partition is in memory, false if it is spilled.

getNumOccupiedMemorySegments

public int getNumOccupiedMemorySegments()

Gets the number of memory segments used by this partition, which includes build side memory buffers and overflow memory segments.

Returns:

The number of occupied memory segments.

getBuildSideBlockCount

public int getBuildSideBlockCount()

getProbeSideBlockCount

public int getProbeSideBlockCount()

getBuildSideRecordCount

public long getBuildSideRecordCount()

getProbeSideRecordCount

public long getProbeSideRecordCount()

getBuildSideChannel

public BlockChannelWriter<MemorySegment> getBuildSideChannel()

getProbeSideChannel

public BlockChannelWriter<MemorySegment> getProbeSideChannel()

insertIntoBuildBuffer

public final long insertIntoBuildBuffer(BT record)
                                 throws IOException

Inserts the given object into the current buffer. This method returns a pointer that can be used to address the written record in this partition, if it is in-memory. The returned pointers have no expressiveness in the case where the partition is spilled.

Parameters:

record - The object to be written to the partition.

Returns:

A pointer to the object in the partition, or -1, if the partition is spilled.

Throws:

IOException - Thrown, when this is a spilled partition and the write failed.

insertIntoProbeBuffer

public final void insertIntoProbeBuffer(PT record)
                                 throws IOException

Inserts the given record into the probe side buffers. This method is only applicable when the partition was spilled while processing the build side.

If this method is invoked when the partition is still being built, it has undefined behavior.

Parameters:

record - The record to be inserted into the probe side buffers.

Throws:

IOException - Thrown, if the buffer is full, needs to be spilled, and spilling causes an error.

spillPartition

public int spillPartition(List<MemorySegment> target,
                          IOManager ioAccess,
                          FileIOChannel.ID targetChannel,
                          LinkedBlockingQueue<MemorySegment> bufferReturnQueue)
                   throws IOException

Spills this partition to disk and sets it up such that it continues spilling records that are added to it. The spilling process must free at least one buffer, either in the partition's record buffers, or in the memory segments for overflow buckets. The partition immediately takes back one buffer to use it for further spilling.

Parameters:

target - The list to which memory segments from overflow buckets are added.

ioAccess - The I/O manager to be used to create a writer to disk.

targetChannel - The id of the target channel for this partition.

Returns:

The number of buffers that were freed by spilling this partition.

Throws:

IOException - Thrown, if the writing failed.

finalizeBuildPhase

public void finalizeBuildPhase(IOManager ioAccess,
                               FileIOChannel.Enumerator probeChannelEnumerator,
                               LinkedBlockingQueue<MemorySegment> bufferReturnQueue)
                        throws IOException

Throws:

IOException

finalizeProbePhase

public int finalizeProbePhase(List<MemorySegment> freeMemory,
                              List<HashPartition<BT,PT>> spilledPartitions,
                              boolean keepUnprobedSpilledPartitions)
                       throws IOException

Parameters:

keepUnprobedSpilledPartitions - If true then partitions that were spilled but received no further probe requests will be retained; used for build-side outer joins.

Returns:

The number of write-behind buffers reclaimable after this method call.

Throws:

IOException

clearAllMemory

public void clearAllMemory(List<MemorySegment> target)

prepareProbePhase

public void prepareProbePhase(IOManager ioAccess,
                              FileIOChannel.Enumerator probeChannelEnumerator,
                              LinkedBlockingQueue<MemorySegment> bufferReturnQueue)
                       throws IOException

Throws:

IOException

setReadPosition

public void setReadPosition(long pointer)

Description copied from interface: SeekableDataInputView

Sets the read pointer to the given position.

Specified by:

setReadPosition in interface SeekableDataInputView

Parameters:

pointer - The new read position.

nextSegment

protected MemorySegment nextSegment(MemorySegment current)
                             throws IOException

Description copied from class: AbstractPagedInputView

The method by which concrete subclasses realize page crossing. This method is invoked when the current page is exhausted and a new page is required to continue the reading. If no further page is available, this method must throw an EOFException.

Specified by:

nextSegment in class AbstractPagedInputView

Parameters:

current - The current page that was read to its limit. May be null, if this method is invoked for the first time.

Returns:

The next page from which the reading should continue. May not be null. If the input is exhausted, an EOFException must be thrown instead.

Throws:

EOFException - Thrown, if no further segment is available.

IOException - Thrown, if the method cannot provide the next page due to an I/O related problem.

getLimitForSegment

protected int getLimitForSegment(MemorySegment segment)

Description copied from class: AbstractPagedInputView

Gets the limit for reading bytes from the given memory segment. This method must return the position of the byte after the last valid byte in the given memory segment. When the position returned by this method is reached, the view will attempt to switch to the next memory segment.

Specified by:

getLimitForSegment in class AbstractPagedInputView

Parameters:

segment - The segment to determine the limit for.

Returns:

The limit for the given memory segment.