HUSTERGS commented on code in PR #14896: URL: https://github.com/apache/lucene/pull/14896#discussion_r2192661153
########## lucene/benchmark-jmh/src/java/org/apache/lucene/benchmark/jmh/CompetitiveBenchmark.java: ########## @@ -0,0 +1,165 @@ +/* + * 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.lucene.benchmark.jmh; + +import java.util.Arrays; +import java.util.SplittableRandom; +import java.util.concurrent.TimeUnit; +import java.util.function.IntSupplier; +import org.apache.lucene.util.ArrayUtil; +import org.apache.lucene.util.VectorUtil; +import org.openjdk.jmh.annotations.Benchmark; +import org.openjdk.jmh.annotations.BenchmarkMode; +import org.openjdk.jmh.annotations.Fork; +import org.openjdk.jmh.annotations.Level; +import org.openjdk.jmh.annotations.Measurement; +import org.openjdk.jmh.annotations.Mode; +import org.openjdk.jmh.annotations.OutputTimeUnit; +import org.openjdk.jmh.annotations.Param; +import org.openjdk.jmh.annotations.Scope; +import org.openjdk.jmh.annotations.Setup; +import org.openjdk.jmh.annotations.State; +import org.openjdk.jmh.annotations.Warmup; + +@BenchmarkMode(Mode.Throughput) +@OutputTimeUnit(TimeUnit.MILLISECONDS) +@State(Scope.Benchmark) +@Warmup(iterations = 3, time = 1) +@Measurement(iterations = 5, time = 1) +@Fork( + value = 1, + jvmArgsAppend = { + "-Xmx1g", + "-Xms1g", + "-XX:+AlwaysPreTouch", + "--add-modules", + "jdk.incubator.vector" + }) +public class CompetitiveBenchmark { + + private final SplittableRandom R = new SplittableRandom(0); + + @Param("128") + int size; + + double[] scores; + int[] docs; + + // scores generated by nextDouble() locate in range [0, 1), so we can tune this parameter and + // see how the performance changes depends on how selective the filter is. + @Param({"0", "0.2", "0.4", "0.5", "0.8"}) + double minScoreInclusive; + + @Setup(Level.Trial) + public void setUpTrial() { + scores = new double[size]; + docs = new int[size]; + } + + @Setup(Level.Invocation) + public void setUpInvocation() { + for (int i = 0; i < size; i++) { + docs[i] = R.nextInt(Integer.MAX_VALUE); + scores[i] = R.nextDouble(); + } + } + + @Benchmark + public int baseline() { + int newSize = 0; + for (int i = 0; i < size; ++i) { + if (scores[i] >= minScoreInclusive) { + docs[newSize] = docs[i]; + scores[newSize] = scores[i]; + newSize++; + } + } + return newSize; + } + + @Benchmark + public int branchlessCandidate() { + int newSize = 0; + for (int i = 0; i < size; ++i) { + int inc = scores[i] >= minScoreInclusive ? 1 : 0; + docs[newSize] = docs[i]; + scores[newSize] = scores[i]; + newSize += inc; + } + return newSize; + } + + // This is an effort try to make the modification of newSize using cmov + // see https://github.com/apache/lucene/pull/14906 + @Benchmark + public int branchlessCandidateCmov() { + int newSize = 0; + for (int i = 0; i < size; ++i) { + int doc = docs[i]; + double score = scores[i]; + docs[newSize] = doc; + scores[newSize] = score; + if (score >= minScoreInclusive) { + newSize += 1; + } + } + return newSize; + } + + @Benchmark + public int vectorizedCandidate() { + return VectorUtil.filterByScore(docs, scores, minScoreInclusive, size); + } + + public static void main(String[] args) { + CompetitiveBenchmark baseline = new CompetitiveBenchmark(); + baseline.size = 128; + baseline.setUpTrial(); + baseline.setUpInvocation(); + int baselineSize = baseline.baseline(); + + CompetitiveBenchmark candidate = new CompetitiveBenchmark(); + candidate.size = 128; + candidate.setUpTrial(); + candidate.setUpInvocation(); + + for (IntSupplier s : + new IntSupplier[] {candidate::branchlessCandidate, candidate::vectorizedCandidate}) { Review Comment: Oh, I forgot that ! -- 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: issues-unsubscr...@lucene.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: issues-unsubscr...@lucene.apache.org For additional commands, e-mail: issues-h...@lucene.apache.org
