mshahid6 commented on code in PR #19225: URL: https://github.com/apache/druid/pull/19225#discussion_r3290093788
########## server/src/main/java/org/apache/druid/server/scheduling/WeightedQueryLaningStrategy.java: ########## @@ -0,0 +1,236 @@ +/* + * 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.druid.server.scheduling; + +import com.fasterxml.jackson.annotation.JsonCreator; +import com.fasterxml.jackson.annotation.JsonProperty; +import com.google.common.base.Preconditions; +import it.unimi.dsi.fastutil.objects.Object2IntArrayMap; +import it.unimi.dsi.fastutil.objects.Object2IntMap; +import org.apache.druid.client.SegmentServerSelector; +import org.apache.druid.java.util.common.DateTimes; +import org.apache.druid.query.Query; +import org.apache.druid.query.QueryPlus; +import org.apache.druid.server.QueryLaningStrategy; +import org.apache.druid.server.QueryScheduler; +import org.joda.time.DateTime; +import org.joda.time.Duration; +import org.joda.time.Period; +import org.joda.time.base.AbstractInterval; + +import javax.annotation.Nullable; +import java.util.Map; +import java.util.Objects; +import java.util.Optional; +import java.util.Set; + +/** + * Query laning strategy that scores queries by how many configured thresholds they breach, + * then assigns them to the most restrictive matching lane. This provides more nuanced lane + * assignment than {@link HiLoQueryLaningStrategy}, which uses a binary high/low split. + * + * <p>Configuration example: + * <pre>{@code + * { + * "strategy": "weighted", + * "periodThreshold": "P1M", + * "segmentCountThreshold": 1000, + * "lanes": { + * "low": { "minScore": 1, "maxPercent": 30 }, + * "very-low": { "minScore": 3, "maxPercent": 10 } + * } + * } + * }</pre> + */ +public class WeightedQueryLaningStrategy implements QueryLaningStrategy +{ + private static final int DEFAULT_SEGMENT_THRESHOLD = Integer.MAX_VALUE; + + private final int segmentCountThreshold; + @Nullable + private final Period periodThreshold; + @Nullable + private final Duration durationThreshold; + @Nullable + private final Duration segmentRangeThreshold; + + @JsonProperty + private final Map<String, LaneConfig> lanes; + + @JsonCreator + public WeightedQueryLaningStrategy( + @JsonProperty("periodThreshold") @Nullable String periodThreshold, + @JsonProperty("durationThreshold") @Nullable String durationThreshold, + @JsonProperty("segmentCountThreshold") @Nullable Integer segmentCountThreshold, + @JsonProperty("segmentRangeThreshold") @Nullable String segmentRangeThreshold, + @JsonProperty("lanes") Map<String, LaneConfig> lanes + ) + { + Preconditions.checkArgument( + segmentCountThreshold != null || periodThreshold != null || durationThreshold != null || segmentRangeThreshold != null, + "At least one of periodThreshold, durationThreshold, segmentCountThreshold, or segmentRangeThreshold must be set" + ); + Preconditions.checkArgument( + lanes != null && !lanes.isEmpty(), + "At least one lane must be defined" + ); + Preconditions.checkArgument( + lanes.keySet().stream().noneMatch(QueryScheduler.TOTAL::equals), + "Lane cannot be named 'total'" + ); + Preconditions.checkArgument( + lanes.keySet().stream().noneMatch("default"::equals), + "Lane cannot be named 'default'" + ); + + this.segmentCountThreshold = segmentCountThreshold == null ? DEFAULT_SEGMENT_THRESHOLD : segmentCountThreshold; + this.periodThreshold = periodThreshold == null ? null : new Period(periodThreshold); + this.durationThreshold = durationThreshold == null + ? null + : new Period(durationThreshold).toStandardDuration(); + this.segmentRangeThreshold = segmentRangeThreshold == null + ? null + : new Period(segmentRangeThreshold).toStandardDuration(); + this.lanes = lanes; + } + + @Override + public Object2IntMap<String> getLaneLimits(int totalLimit) + { + Object2IntMap<String> limits = new Object2IntArrayMap<>(lanes.size()); + for (Map.Entry<String, LaneConfig> entry : lanes.entrySet()) { + limits.put(entry.getKey(), computeLimitFromPercent(totalLimit, entry.getValue().maxPercent)); + } + return limits; + } + + @Override + public <T> Optional<String> computeLane(QueryPlus<T> query, Set<SegmentServerSelector> segments) + { + final String existingLane = query.getQuery().context().getLane(); + if (existingLane != null) { + return Optional.of(existingLane); + } + + int score = computeScore(query.getQuery(), segments); + if (score == 0) { + return Optional.empty(); + } + + // Find the lane with the highest minScore that this query meets + String bestLane = null; + int bestMinScore = 0; + for (Map.Entry<String, LaneConfig> entry : lanes.entrySet()) { + int minScore = entry.getValue().minScore; + if (score >= minScore && minScore > bestMinScore) { + bestLane = entry.getKey(); + bestMinScore = minScore; + } + } + return Optional.ofNullable(bestLane); + } + + private <T> int computeScore(Query<T> query, Set<SegmentServerSelector> segments) Review Comment: SG -- 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]
