org.apache.spark.storage

Class PushBasedFetchHelper

Object

org.apache.spark.storage.PushBasedFetchHelper

All Implemented Interfaces:

org.apache.spark.internal.Logging

public class PushBasedFetchHelper
extends Object
implements org.apache.spark.internal.Logging

Helper class for ShuffleBlockFetcherIterator that encapsulates all the push-based functionality to fetch push-merged block meta and shuffle chunks. A push-merged block contains multiple shuffle chunks where each shuffle chunk contains multiple shuffle blocks that belong to the common reduce partition and were merged by the external shuffle service to that chunk.

Nested Class Summary

Nested classes/interfaces inherited from interface org.apache.spark.internal.Logging

org.apache.spark.internal.Logging.SparkShellLoggingFilter

Constructor Summary

Constructors

Constructor and Description
PushBasedFetchHelper(org.apache.spark.storage.ShuffleBlockFetcherIterator iterator, org.apache.spark.network.shuffle.BlockStoreClient shuffleClient, org.apache.spark.storage.BlockManager blockManager, org.apache.spark.MapOutputTracker mapOutputTracker)

Method Summary

Modifier and Type	Method and Description
void	addChunk(ShuffleBlockChunkId blockId, org.roaringbitmap.RoaringBitmap chunkMeta) This is executed by the task thread when the iterator.next() is invoked and the iterator processes a response of type ShuffleBlockFetcherIterator.PushMergedLocalMetaFetchResult.
scala.collection.mutable.ArrayBuffer<scala.Tuple3<BlockId,Object,Object>>	createChunkBlockInfosFromMetaResponse(int shuffleId, int shuffleMergeId, int reduceId, long blockSize, org.roaringbitmap.RoaringBitmap[] bitmaps) This is executed by the task thread when the iterator.next() is invoked and the iterator processes a response of type ShuffleBlockFetcherIterator.PushMergedRemoteMetaFetchResult.
void	fetchAllPushMergedLocalBlocks(scala.collection.mutable.LinkedHashSet<BlockId> pushMergedLocalBlocks) This is executed by the task thread when the iterator is initialized.
void	initiateFallbackFetchForPushMergedBlock(BlockId blockId, BlockManagerId address) This is executed by the task thread when the iterator.next() is invoked and the iterator processes a response of type: 1) ShuffleBlockFetcherIterator.SuccessFetchResult 2) ShuffleBlockFetcherIterator.FallbackOnPushMergedFailureResult 3) ShuffleBlockFetcherIterator.PushMergedRemoteMetaFailedFetchResult
boolean	isLocalPushMergedBlockAddress(BlockManagerId address) Returns true if the address is of a push-merged-local block.
boolean	isPushMergedShuffleBlockAddress(BlockManagerId address) Returns true if the address is for a push-merged block.
boolean	isRemotePushMergedBlockAddress(BlockManagerId address) Returns true if the address is of a remote push-merged block.
void	removeChunk(ShuffleBlockChunkId blockId) This is executed by the task thread when the iterator.next() is invoked and the iterator processes a response of type ShuffleBlockFetcherIterator.SuccessFetchResult.
void	sendFetchMergedStatusRequest(org.apache.spark.storage.ShuffleBlockFetcherIterator.FetchRequest req) This is executed by the task thread when the iterator is initialized and only if it has push-merged blocks for which it needs to fetch the metadata.

Methods inherited from class Object

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

Methods inherited from interface org.apache.spark.internal.Logging

$init$, initializeForcefully, initializeLogIfNecessary, initializeLogIfNecessary, initializeLogIfNecessary$default$2, initLock, isTraceEnabled, log, logDebug, logDebug, logError, logError, logInfo, logInfo, logName, logTrace, logTrace, logWarning, logWarning, org$apache$spark$internal$Logging$$log__$eq, org$apache$spark$internal$Logging$$log_, uninitialize

Constructor Detail

PushBasedFetchHelper

public PushBasedFetchHelper(org.apache.spark.storage.ShuffleBlockFetcherIterator iterator,
                            org.apache.spark.network.shuffle.BlockStoreClient shuffleClient,
                            org.apache.spark.storage.BlockManager blockManager,
                            org.apache.spark.MapOutputTracker mapOutputTracker)

Method Detail

addChunk

public void addChunk(ShuffleBlockChunkId blockId,
                     org.roaringbitmap.RoaringBitmap chunkMeta)

This is executed by the task thread when the iterator.next() is invoked and the iterator processes a response of type ShuffleBlockFetcherIterator.PushMergedLocalMetaFetchResult.

Parameters:

blockId - shuffle chunk id.

chunkMeta - (undocumented)

createChunkBlockInfosFromMetaResponse

public scala.collection.mutable.ArrayBuffer<scala.Tuple3<BlockId,Object,Object>> createChunkBlockInfosFromMetaResponse(int shuffleId,
                                                                                                                       int shuffleMergeId,
                                                                                                                       int reduceId,
                                                                                                                       long blockSize,
                                                                                                                       org.roaringbitmap.RoaringBitmap[] bitmaps)

This is executed by the task thread when the iterator.next() is invoked and the iterator processes a response of type ShuffleBlockFetcherIterator.PushMergedRemoteMetaFetchResult.

Parameters:

shuffleId - shuffle id.

reduceId - reduce id.

blockSize - size of the push-merged block.

bitmaps - chunk bitmaps, where each bitmap contains all the mapIds that were merged to that chunk.

shuffleMergeId - (undocumented)

Returns:

shuffle chunks to fetch.

fetchAllPushMergedLocalBlocks

public void fetchAllPushMergedLocalBlocks(scala.collection.mutable.LinkedHashSet<BlockId> pushMergedLocalBlocks)

This is executed by the task thread when the iterator is initialized. It fetches all the outstanding push-merged local blocks.

Parameters:

pushMergedLocalBlocks - set of identified merged local blocks and their sizes.

initiateFallbackFetchForPushMergedBlock

public void initiateFallbackFetchForPushMergedBlock(BlockId blockId,
                                                    BlockManagerId address)

This is executed by the task thread when the iterator.next() is invoked and the iterator processes a response of type: 1) ShuffleBlockFetcherIterator.SuccessFetchResult 2) ShuffleBlockFetcherIterator.FallbackOnPushMergedFailureResult 3) ShuffleBlockFetcherIterator.PushMergedRemoteMetaFailedFetchResult

This initiates fetching fallback blocks for a push-merged block or a shuffle chunk that failed to fetch. It makes a call to the map output tracker to get the list of original blocks for the given push-merged block/shuffle chunk, split them into remote and local blocks, and process them accordingly. It also updates the numberOfBlocksToFetch in the iterator as it processes failed response and finds more push-merged requests to remote and again updates it with additional requests for original blocks. The fallback happens when: 1. There is an exception while creating shuffle chunks from push-merged-local shuffle block. See fetchLocalBlock. 2. There is a failure when fetching remote shuffle chunks. 3. There is a failure when processing SuccessFetchResult which is for a shuffle chunk (local or remote).

Parameters:

blockId - (undocumented)

address - (undocumented)

isLocalPushMergedBlockAddress

public boolean isLocalPushMergedBlockAddress(BlockManagerId address)

Returns true if the address is of a push-merged-local block. false otherwise.

Parameters:

address - (undocumented)

Returns:

(undocumented)

isPushMergedShuffleBlockAddress

public boolean isPushMergedShuffleBlockAddress(BlockManagerId address)

Returns true if the address is for a push-merged block.

Parameters:

address - (undocumented)

Returns:

(undocumented)

isRemotePushMergedBlockAddress

public boolean isRemotePushMergedBlockAddress(BlockManagerId address)

Returns true if the address is of a remote push-merged block. false otherwise.

Parameters:

address - (undocumented)

Returns:

(undocumented)

removeChunk

public void removeChunk(ShuffleBlockChunkId blockId)

This is executed by the task thread when the iterator.next() is invoked and the iterator processes a response of type ShuffleBlockFetcherIterator.SuccessFetchResult.

Parameters:

blockId - shuffle chunk id.

sendFetchMergedStatusRequest

public void sendFetchMergedStatusRequest(org.apache.spark.storage.ShuffleBlockFetcherIterator.FetchRequest req)

This is executed by the task thread when the iterator is initialized and only if it has push-merged blocks for which it needs to fetch the metadata.

Parameters:

req - ShuffleBlockFetcherIterator.FetchRequest that only contains requests to fetch metadata of push-merged blocks.