dwsmith1983 commented on code in PR #6785: URL: https://github.com/apache/datafusion-comet/pull/6785#discussion_r4371614203
########## spark/src/main/scala/org/apache/comet/rules/CometShuffledHashJoinStrategy.scala: ########## @@ -0,0 +1,175 @@ +/* + * 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.comet.rules + +import org.apache.spark.sql.SparkSession +import org.apache.spark.sql.catalyst.expressions.RowOrdering +import org.apache.spark.sql.catalyst.optimizer.{BuildLeft, BuildRight, BuildSide} +import org.apache.spark.sql.catalyst.planning.ExtractEquiJoinKeys +import org.apache.spark.sql.catalyst.plans.{ExistenceJoin, LeftSemi} +import org.apache.spark.sql.catalyst.plans.logical.{Join, JoinHint, JoinStrategyHint, LogicalPlan} +import org.apache.spark.sql.execution.{SparkPlan, SparkStrategy} +import org.apache.spark.sql.execution.adaptive.{BroadcastQueryStageExec, LogicalQueryStage} +import org.apache.spark.sql.execution.joins.{ShuffledHashJoinExec, SortMergeJoinExec} +import org.apache.spark.sql.internal.SQLConf + +import org.apache.comet.CometConf +import org.apache.comet.CometSparkSessionExtensions.{isCometLoaded, withFallbackReason, withInfo} +import org.apache.comet.shims.ShimJoinSelection + +/** + * Plans a ShuffledHashJoinExec in place of a SortMergeJoinExec, before EnsureRequirements and + * RemoveRedundantSorts, so the sorts above the join survive. Adapted from Apache Gluten. + */ +case class CometShuffledHashJoinStrategy(session: SparkSession) + extends SparkStrategy + with ShimJoinSelection { + + override def apply(plan: LogicalPlan): Seq[SparkPlan] = plan match { + case join: Join if isEnabled(join) => planJoin(join) + case _ => Nil + } + + private def sqlConf: SQLConf = session.sessionState.conf + + // Planner strategies run with Comet off and before CometRule, which applies plan-only mode. + private def isEnabled(join: Join): Boolean = + CometConf.COMET_FORCE_SHJ.get(sqlConf) && + CometConf.COMET_EXEC_ENABLED.get(sqlConf) && + !CometConf.COMET_EXPLAIN_PLAN_ONLY_ENABLED.get(sqlConf) && + !join.isStreaming && + isCometLoaded(sqlConf) + + private def planJoin(join: Join): Seq[SparkPlan] = join match { + case ExtractEquiJoinKeys(joinType, leftKeys, rightKeys, condition, _, left, right, hint) + if !isLeftToSpark(join, hint) && canSortMergeJoin(joinType) && + RowOrdering.isOrderable(leftKeys) && hashJoinSupportedShim(leftKeys, rightKeys) => + buildSide(join) match { + case Some(BuildRight) if joinType == LeftSemi || joinType.isInstanceOf[ExistenceJoin] => + // LeftSemi https://github.com/apache/datafusion-comet/issues/2667 + // ExistenceJoin https://github.com/apache/datafusion-comet/issues/2697 + planBySpark(join) { smj => + withFallbackReason(smj, declineReason(s"BuildRight with $joinType is not supported")) + } + case Some(side) => + buildSideOverLimit(join, side) match { + case Some(reason) => + // Not a fallback: the kept sort-merge join still runs natively. + planBySpark(join)(smj => withInfo(smj, declineReason(reason))) + case None => + Seq( + ShuffledHashJoinExec( + leftKeys, + rightKeys, + joinType, + side, + condition, + planLater(left), + planLater(right))) + } + case None => Nil + } + case _ => Nil + } + + private def isLeftToSpark(join: Join, hint: JoinHint): Boolean = + isBroadcastStage(join.left) || isBroadcastStage(join.right) || + canPlanAsBroadcastHashJoin(join, sqlConf) || hasStrategyHint(hint) + + // canPlanAsBroadcastHashJoin misses a broadcast stage when the adaptive threshold is lower or + // off, and AQE discards a re-plan that hash joins one. + private def isBroadcastStage(plan: LogicalPlan): Boolean = plan match { + case LogicalQueryStage(_, _: BroadcastQueryStageExec) => true + case _ => false + } + + // AQE's NO_BROADCAST_HASH and PREFER_SHUFFLE_HASH are outside JoinStrategyHint.strategies. + private def hasStrategyHint(hint: JoinHint): Boolean = + Seq(hint.leftHint, hint.rightHint).exists( + _.exists(_.strategy.exists(JoinStrategyHint.strategies.contains))) Review Comment: The strategy now builds on the side AQE hints with `PREFER_SHUFFLE_HASH` when only one buildable side carries it, much as Spark's `getShuffleHashJoinBuildSide` does, and keeps the size comparison when both sides or neither do. A lone `NO_BROADCAST_HASH` is handled as before. `forceShuffledHashJoin builds on the side AQE's PREFER_SHUFFLE_HASH hint names` runs your AQE shape and checks that AQE put the hint on the right side and that the join builds right. `forceShuffledHashJoin builds on the one buildable side PREFER_SHUFFLE_HASH names` calls the strategy with the hint on one side, on both, and on the left side of a LEFT ANTI join, which cannot build there. -- 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. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
