content: /*
   * 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.arrow.algorithm.search;
  
  import java.util.concurrent.ExecutorService;
  import java.util.concurrent.Executors;
  import java.util.concurrent.TimeUnit;
  import org.apache.arrow.memory.BufferAllocator;
  import org.apache.arrow.memory.RootAllocator;
  import org.apache.arrow.vector.IntVector;
  import org.openjdk.jmh.annotations.Benchmark;
  import org.openjdk.jmh.annotations.BenchmarkMode;
  import org.openjdk.jmh.annotations.Level;
  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.TearDown;
  import org.openjdk.jmh.runner.Runner;
  import org.openjdk.jmh.runner.RunnerException;
  import org.openjdk.jmh.runner.options.Options;
  import org.openjdk.jmh.runner.options.OptionsBuilder;
  
  /** Benchmarks for {@link ParallelSearcher}. */
  public class ParallelSearcherBenchmarks {
    // checkstyle:off: MissingJavadocMethod
  
    private static final int VECTOR_LENGTH = 1024 * 1024;
  
    /** State object for the benchmarks. */
    @State(Scope.Benchmark)
    public static class SearchState {
  
      @Param({"1", "2", "5", "10", "20", "50", "100"})
      int numThreads;
  
      BufferAllocator allocator;
  
      ExecutorService threadPool;
  
      IntVector targetVector;
  
      IntVector keyVector;
  
      ParallelSearcher<IntVector> searcher;
  
      @Setup(Level.Trial)
      public void prepare() {
        allocator = new RootAllocator(Integer.MAX_VALUE);
        targetVector = new IntVector("target vector", allocator);
        targetVector.allocateNew(VECTOR_LENGTH);
        keyVector = new IntVector("key vector", allocator);
        keyVector.allocateNew(1);
        threadPool = Executors.newFixedThreadPool(numThreads);
  
        for (int i = 0; i < VECTOR_LENGTH; i++) {
          targetVector.set(i, i);
        }
        targetVector.setValueCount(VECTOR_LENGTH);
  
        keyVector.set(0, VECTOR_LENGTH / 3);
        keyVector.setValueCount(1);
      }
  
      @Setup(Level.Invocation)
      public void prepareInvoke() {
        searcher = new ParallelSearcher<>(targetVector, threadPool, numThreads);
      }
  
      @TearDown(Level.Trial)
      public void tearDownState() {
        targetVector.close();
        keyVector.close();
        allocator.close();
        threadPool.shutdown();
      }
    }
  
    @Benchmark
    @BenchmarkMode(Mode.AverageTime)
    @OutputTimeUnit(TimeUnit.MICROSECONDS)
    public void searchBenchmark(SearchState state) throws Exception {
      state.searcher.search(state.keyVector, 0);
    }
  
    public static void main(String[] args) throws RunnerException {
      Options opt =
          new OptionsBuilder()
              .include(ParallelSearcherBenchmarks.class.getSimpleName())
              .forks(1)
              .build();
  
      new Runner(opt).run();
    }
    // checkstyle:on: MissingJavadocMethod
  }
  