otterc commented on a change in pull request #32140:
URL: https://github.com/apache/spark/pull/32140#discussion_r648845832
##########
File path:
core/src/main/scala/org/apache/spark/storage/ShuffleBlockFetcherIterator.scala
##########
@@ -1124,4 +1392,298 @@ object ShuffleBlockFetcherIterator {
*/
private[storage]
case class DeferFetchRequestResult(fetchRequest: FetchRequest) extends
FetchResult
+
+ /**
+ * Result of a fetch from a remote merged block unsuccessfully.
+ * Instead of treating this as a FailureFetchResult, we ignore this failure
+ * and fallback to fetch the original unmerged blocks.
+ * @param blockId block id
+ * @param address BlockManager that the merged block was attempted to be
fetched from
+ * @param size size of the block, used to update bytesInFlight.
+ * @param isNetworkReqDone Is this the last network request for this host in
this fetch
+ * request. Used to update reqsInFlight.
+ */
+ private[storage] case class IgnoreFetchResult(blockId: BlockId,
+ address: BlockManagerId,
+ size: Long,
+ isNetworkReqDone: Boolean) extends FetchResult
+
+ /**
+ * Result of a successful fetch of meta information for a merged block.
+ *
+ * @param shuffleId shuffle id.
+ * @param reduceId reduce id.
+ * @param blockSize size of each merged block.
+ * @param numChunks number of chunks in the merged block.
+ * @param bitmaps bitmaps for every chunk.
+ * @param address BlockManager that the merged status was fetched
from.
+ */
+ private[storage] case class MergedBlocksMetaFetchResult(
+ shuffleId: Int,
+ reduceId: Int,
+ blockSize: Long,
+ numChunks: Int,
+ bitmaps: Array[RoaringBitmap],
+ address: BlockManagerId,
+ blockId: BlockId = DUMMY_SHUFFLE_BLOCK_ID) extends FetchResult
+
+ /**
+ * Result of a failure while fetching the meta information for a merged
block.
+ *
+ * @param shuffleId shuffle id.
+ * @param reduceId reduce id.
+ * @param address BlockManager that the merged status was fetched from.
+ */
+ private[storage] case class MergedBlocksMetaFailedFetchResult(
+ shuffleId: Int,
+ reduceId: Int,
+ address: BlockManagerId,
+ blockId: BlockId = DUMMY_SHUFFLE_BLOCK_ID) extends FetchResult
+}
+
+/**
+ * Helper class that encapsulates all the push-based functionality to fetch
merged block meta
+ * and merged shuffle block chunks.
+ */
+private class PushBasedFetchHelper(
Review comment:
A lot of methods in `PushBasedFetchHelper` also needs access to the
iterator instance. It needs to work with the iterator to be able to:
1. add results to the iterator's `result` queue when it receives the meta
response.
2. updates number of blocks to fetch.
3. fetch fallback blocks when there is a fallback and this in turn removes
some pending blocks from `fetchRequests`.
It also needs access to the `shuffleClient`, `blockManager`, and
`mapOutputTracker`. Most of the methods in this class will access one or more
of these instances.
Also, each instance of helper contains `chunksMetaMap`. In order to make
`PushBasedFetchHelper` a trait, this would then would move the
`ShuffleBlockFetcherIterator` and then passed to each method in the helper that
needs it.
IMO, it seem better to create an instance of `PushBasedFetchHelper` per
iterator instance. Otherwise, all the methods of `PushBasedFetchHelper` will
have way more arguments.
I find this class similar to the existing `BufferReleasingInputStream` in
the iterator.
##########
File path:
core/src/main/scala/org/apache/spark/storage/PushBasedFetchHelper.scala
##########
@@ -0,0 +1,289 @@
+/*
+ * 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.util.concurrent.TimeUnit
+
+import scala.collection.mutable
+import scala.collection.mutable.ArrayBuffer
+import scala.util.{Failure, Success}
+
+import org.roaringbitmap.RoaringBitmap
+
+import org.apache.spark.MapOutputTracker
+import org.apache.spark.MapOutputTracker.SHUFFLE_PUSH_MAP_ID
+import org.apache.spark.internal.Logging
+import org.apache.spark.network.buffer.ManagedBuffer
+import org.apache.spark.network.shuffle.{BlockStoreClient, MergedBlockMeta,
MergedBlocksMetaListener}
+import org.apache.spark.storage.BlockManagerId.SHUFFLE_MERGER_IDENTIFIER
+import org.apache.spark.storage.ShuffleBlockFetcherIterator._
+
+/**
+ * Helper class for [[ShuffleBlockFetcherIterator]] that encapsulates all the
push-based
+ * functionality to fetch merged block meta and merged shuffle block chunks.
+ */
+private class PushBasedFetchHelper(
+ private val iterator: ShuffleBlockFetcherIterator,
+ private val shuffleClient: BlockStoreClient,
+ private val blockManager: BlockManager,
+ private val mapOutputTracker: MapOutputTracker) extends Logging {
+
+ private[this] val startTimeNs = System.nanoTime()
+
+ private[this] val localShuffleMergerBlockMgrId = BlockManagerId(
+ SHUFFLE_MERGER_IDENTIFIER, blockManager.blockManagerId.host,
+ blockManager.blockManagerId.port, blockManager.blockManagerId.topologyInfo)
+
+ /** A map for storing merged block shuffle chunk bitmap */
+ private[this] val chunksMetaMap = new mutable.HashMap[ShuffleBlockChunkId,
RoaringBitmap]()
Review comment:
I took another look at it and I think making it a `ConcurrentMap` and
swapping the order of those lines fix any issues related to multiple thread.
PTAL.
##########
File path:
core/src/main/scala/org/apache/spark/storage/PushBasedFetchHelper.scala
##########
@@ -0,0 +1,289 @@
+/*
+ * 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.util.concurrent.TimeUnit
+
+import scala.collection.mutable
+import scala.collection.mutable.ArrayBuffer
+import scala.util.{Failure, Success}
+
+import org.roaringbitmap.RoaringBitmap
+
+import org.apache.spark.MapOutputTracker
+import org.apache.spark.MapOutputTracker.SHUFFLE_PUSH_MAP_ID
+import org.apache.spark.internal.Logging
+import org.apache.spark.network.buffer.ManagedBuffer
+import org.apache.spark.network.shuffle.{BlockStoreClient, MergedBlockMeta,
MergedBlocksMetaListener}
+import org.apache.spark.storage.BlockManagerId.SHUFFLE_MERGER_IDENTIFIER
+import org.apache.spark.storage.ShuffleBlockFetcherIterator._
+
+/**
+ * Helper class for [[ShuffleBlockFetcherIterator]] that encapsulates all the
push-based
+ * functionality to fetch merged block meta and merged shuffle block chunks.
+ */
+private class PushBasedFetchHelper(
+ private val iterator: ShuffleBlockFetcherIterator,
+ private val shuffleClient: BlockStoreClient,
+ private val blockManager: BlockManager,
+ private val mapOutputTracker: MapOutputTracker) extends Logging {
+
+ private[this] val startTimeNs = System.nanoTime()
+
+ private[this] val localShuffleMergerBlockMgrId = BlockManagerId(
+ SHUFFLE_MERGER_IDENTIFIER, blockManager.blockManagerId.host,
+ blockManager.blockManagerId.port, blockManager.blockManagerId.topologyInfo)
+
+ /** A map for storing merged block shuffle chunk bitmap */
+ private[this] val chunksMetaMap = new mutable.HashMap[ShuffleBlockChunkId,
RoaringBitmap]()
+
+ /**
+ * Returns true if the address is for a push-merged block.
+ */
+ def isMergedShuffleBlockAddress(address: BlockManagerId): Boolean = {
+ SHUFFLE_MERGER_IDENTIFIER.equals(address.executorId)
+ }
+
+ /**
+ * Returns true if the address is not of executor local or merged local
block. false otherwise.
+ */
+ def isNotExecutorOrMergedLocal(address: BlockManagerId): Boolean = {
+ (isMergedShuffleBlockAddress(address) && address.host !=
blockManager.blockManagerId.host) ||
+ (!isMergedShuffleBlockAddress(address) && address !=
blockManager.blockManagerId)
+ }
+
+ /**
+ * Returns true if the address if of merged local block. false otherwise.
+ */
+ def isMergedLocal(address: BlockManagerId): Boolean = {
+ isMergedShuffleBlockAddress(address) && address.host ==
blockManager.blockManagerId.host
+ }
+
+ def getNumberOfBlocksInChunk(blockId : ShuffleBlockChunkId): Int = {
+ chunksMetaMap(blockId).getCardinality
+ }
+
+ def removeChunk(blockId: ShuffleBlockChunkId): Unit = {
+ chunksMetaMap.remove(blockId)
+ }
+
+ def createChunkBlockInfosFromMetaResponse(
+ shuffleId: Int,
+ reduceId: Int,
+ blockSize: Long,
+ numChunks: Int,
+ bitmaps: Array[RoaringBitmap]): ArrayBuffer[(BlockId, Long, Int)] = {
+ val approxChunkSize = blockSize / numChunks
+ val blocksToFetch = new ArrayBuffer[(BlockId, Long, Int)]()
+ for (i <- 0 until numChunks) {
+ val blockChunkId = ShuffleBlockChunkId(shuffleId, reduceId, i)
+ chunksMetaMap.put(blockChunkId, bitmaps(i))
+ logDebug(s"adding block chunk $blockChunkId of size $approxChunkSize")
+ blocksToFetch += ((blockChunkId, approxChunkSize, SHUFFLE_PUSH_MAP_ID))
+ }
+ blocksToFetch
+ }
+
+ def sendFetchMergedStatusRequest(req: FetchRequest): Unit = {
+ val sizeMap = req.blocks.map {
+ case FetchBlockInfo(blockId, size, _) =>
+ val shuffleBlockId = blockId.asInstanceOf[ShuffleBlockId]
+ ((shuffleBlockId.shuffleId, shuffleBlockId.reduceId), size)}.toMap
+ val address = req.address
+ val mergedBlocksMetaListener = new MergedBlocksMetaListener {
+ override def onSuccess(shuffleId: Int, reduceId: Int, meta:
MergedBlockMeta): Unit = {
+ logInfo(s"Received the meta of merged block for ($shuffleId,
$reduceId) " +
+ s"from ${req.address.host}:${req.address.port}")
+ try {
+ iterator.addToResultsQueue(MergedBlocksMetaFetchResult(shuffleId,
reduceId,
+ sizeMap((shuffleId, reduceId)), meta.getNumChunks,
meta.readChunkBitmaps(), address))
+ } catch {
+ case exception: Throwable =>
+ logError(s"Failed to parse the meta of merged block for
($shuffleId, $reduceId) " +
+ s"from ${req.address.host}:${req.address.port}", exception)
+ iterator.addToResultsQueue(
+ MergedBlocksMetaFailedFetchResult(shuffleId, reduceId, address))
+ }
+ }
+
+ override def onFailure(shuffleId: Int, reduceId: Int, exception:
Throwable): Unit = {
+ logError(s"Failed to get the meta of merged block for ($shuffleId,
$reduceId) " +
+ s"from ${req.address.host}:${req.address.port}", exception)
+
iterator.addToResultsQueue(MergedBlocksMetaFailedFetchResult(shuffleId,
reduceId, address))
+ }
+ }
+ req.blocks.foreach { block =>
+ val shuffleBlockId = block.blockId.asInstanceOf[ShuffleBlockId]
+ shuffleClient.getMergedBlockMeta(address.host, address.port,
shuffleBlockId.shuffleId,
+ shuffleBlockId.reduceId, mergedBlocksMetaListener)
+ }
+ }
+
+ // Fetch all outstanding merged local blocks
+ def fetchAllMergedLocalBlocks(
+ mergedLocalBlocks: mutable.LinkedHashSet[BlockId]): Unit = {
+ if (mergedLocalBlocks.nonEmpty) {
+ blockManager.hostLocalDirManager.foreach(fetchMergedLocalBlocks(_,
mergedLocalBlocks))
+ }
+ }
+
+ /**
+ * Fetch the merged blocks dirs if they are not in the cache and eventually
fetch merged local
+ * blocks.
+ */
+ private def fetchMergedLocalBlocks(
+ hostLocalDirManager: HostLocalDirManager,
+ mergedLocalBlocks: mutable.LinkedHashSet[BlockId]): Unit = {
+ val cachedMergerDirs = hostLocalDirManager.getCachedHostLocalDirs.get(
+ SHUFFLE_MERGER_IDENTIFIER)
+ if (cachedMergerDirs.isDefined) {
+ logDebug(s"Fetching local merged blocks with cached executors dir: " +
+ s"${cachedMergerDirs.get.mkString(", ")}")
+ mergedLocalBlocks.foreach(blockId =>
+ fetchMergedLocalBlock(blockId, cachedMergerDirs.get,
localShuffleMergerBlockMgrId))
+ } else {
+ logDebug(s"Asynchronous fetching local merged blocks without cached
executors dir")
+ hostLocalDirManager.getHostLocalDirs(localShuffleMergerBlockMgrId.host,
+ localShuffleMergerBlockMgrId.port, Array(SHUFFLE_MERGER_IDENTIFIER)) {
+ case Success(dirs) =>
+ mergedLocalBlocks.takeWhile {
+ blockId =>
+ logDebug(s"Successfully fetched local dirs: " +
+ s"${dirs.get(SHUFFLE_MERGER_IDENTIFIER).mkString(", ")}")
+ fetchMergedLocalBlock(blockId, dirs(SHUFFLE_MERGER_IDENTIFIER),
+ localShuffleMergerBlockMgrId)
+ }
+ logDebug(s"Got local merged blocks (without cached executors' dir)
in " +
+ s"${TimeUnit.NANOSECONDS.toMillis(System.nanoTime() -
startTimeNs)} ms")
+ case Failure(throwable) =>
+ // If we see an exception with getting the local dirs for local
merged blocks,
+ // we fallback to fetch the original unmerged blocks. We do not
report block fetch
+ // failure.
+ logWarning(s"Error occurred while getting the local dirs for local
merged " +
+ s"blocks: ${mergedLocalBlocks.mkString(", ")}. Fetch the original
blocks instead",
+ throwable)
+ mergedLocalBlocks.foreach(
+ blockId => iterator.addToResultsQueue(
+ IgnoreFetchResult(blockId, localShuffleMergerBlockMgrId, 0,
isNetworkReqDone = false))
+ )
+ }
+ }
+ }
+
+ /**
+ * Fetch a single local merged block generated.
+ * @param blockId ShuffleBlockId to be fetched
+ * @param localDirs Local directories where the merged shuffle files are
stored
+ * @param blockManagerId BlockManagerId
+ * @return Boolean represents successful or failed fetch
+ */
+ private[this] def fetchMergedLocalBlock(
+ blockId: BlockId,
+ localDirs: Array[String],
+ blockManagerId: BlockManagerId): Boolean = {
+ try {
+ val shuffleBlockId = blockId.asInstanceOf[ShuffleBlockId]
+ val chunksMeta = blockManager.getMergedBlockMeta(shuffleBlockId,
localDirs)
+ .readChunkBitmaps()
+ // Fetch local merged shuffle block data as multiple chunks
+ val bufs: Seq[ManagedBuffer] =
blockManager.getMergedBlockData(shuffleBlockId, localDirs)
+ // Update total number of blocks to fetch, reflecting the multiple local
chunks
+ iterator.foundMoreBlocksToFetch(bufs.size - 1)
+ for (chunkId <- bufs.indices) {
+ val buf = bufs(chunkId)
+ buf.retain()
+ val shuffleChunkId = ShuffleBlockChunkId(shuffleBlockId.shuffleId,
+ shuffleBlockId.reduceId, chunkId)
+ iterator.addToResultsQueue(
+ SuccessFetchResult(shuffleChunkId, SHUFFLE_PUSH_MAP_ID,
blockManagerId, buf.size(), buf,
+ isNetworkReqDone = false))
+ chunksMetaMap.put(shuffleChunkId, chunksMeta(chunkId))
+ }
+ true
+ } catch {
+ case e: Exception =>
+ // If we see an exception with reading a local merged block, we
fallback to
+ // fetch the original unmerged blocks. We do not report block fetch
failure
+ // and will continue with the remaining local block read.
+ logWarning(s"Error occurred while fetching local merged block, " +
+ s"prepare to fetch the original blocks", e)
+ iterator.addToResultsQueue(
+ IgnoreFetchResult(blockId, blockManagerId, 0, isNetworkReqDone =
false))
+ false
+ }
+ }
+
+ /**
+ * Initiate fetching fallback blocks for a merged block (or a merged block
chunk) that's failed
+ * to fetch.
+ * It calls out to map output tracker to get the list of original blocks for
the
+ * given merged blocks, split them into remote and local blocks, and process
them
+ * accordingly.
+ * The fallback happens when:
+ * 1. There is an exception while creating shuffle block chunk from local
merged shuffle block.
+ * See fetchLocalBlock.
+ * 2. There is a failure when fetching remote shuffle block chunks.
+ * 3. There is a failure when processing SuccessFetchResult which is for a
shuffle chunk
+ * (local or remote).
+ *
+ * @return number of blocks processed
+ */
+ def initiateFallbackBlockFetchForMergedBlock(
+ blockId: BlockId,
+ address: BlockManagerId): Int = {
+ logWarning(s"Falling back to fetch the original unmerged blocks for merged
block $blockId")
+ // Increase the blocks processed since we will process another block in
the next iteration of
+ // the while loop in ShuffleBlockFetcherIterator.next().
+ var blocksProcessed = 1
+ val fallbackBlocksByAddr: Iterator[(BlockManagerId, Seq[(BlockId, Long,
Int)])] =
+ if (blockId.isShuffle) {
+ val shuffleBlockId = blockId.asInstanceOf[ShuffleBlockId]
+ mapOutputTracker.getMapSizesForMergeResult(
+ shuffleBlockId.shuffleId, shuffleBlockId.reduceId)
+ } else {
+ val shuffleChunkId = blockId.asInstanceOf[ShuffleBlockChunkId]
+ val chunkBitmap: RoaringBitmap =
chunksMetaMap.remove(shuffleChunkId).orNull
+ // When there is a failure to fetch a remote merged shuffle block
chunk, then we try to
+ // fallback not only for that particular remote shuffle block chunk
but also for all the
+ // pending block chunks that belong to the same host. The reason for
doing so is that it is
+ // very likely that the subsequent requests for merged block chunks
from this host will fail
+ // as well. Since, push-based shuffle is best effort and we try not to
increase the delay
+ // of the fetches, we immediately fallback for all the pending shuffle
chunks in the
+ // fetchRequests queue.
+ if (isNotExecutorOrMergedLocal(address)) {
+ // Fallback for all the pending fetch requests
+ val pendingShuffleChunks =
iterator.removePendingChunks(shuffleChunkId, address)
+ if (pendingShuffleChunks.nonEmpty) {
+ pendingShuffleChunks.foreach { pendingBlockId =>
+ logWarning(s"Falling back immediately for merged block
$pendingBlockId")
+ val bitmapOfPendingChunk: RoaringBitmap =
+ chunksMetaMap.remove(pendingBlockId).orNull
+ assert(bitmapOfPendingChunk != null)
+ chunkBitmap.or(bitmapOfPendingChunk)
Review comment:
Resolving this one.
--
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
For queries about this service, please contact Infrastructure at:
[email protected]
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
