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.kafka.jmh.timeline;
  
  import org.apache.kafka.common.utils.LogContext;
  import org.apache.kafka.timeline.SnapshotRegistry;
  import org.apache.kafka.timeline.TimelineHashMap;
  
  import org.openjdk.jmh.annotations.Benchmark;
  import org.openjdk.jmh.annotations.BenchmarkMode;
  import org.openjdk.jmh.annotations.Fork;
  import org.openjdk.jmh.annotations.Measurement;
  import org.openjdk.jmh.annotations.Mode;
  import org.openjdk.jmh.annotations.OutputTimeUnit;
  import org.openjdk.jmh.annotations.Scope;
  import org.openjdk.jmh.annotations.State;
  import org.openjdk.jmh.annotations.Warmup;
  
  import java.util.HashMap;
  import java.util.Map;
  import java.util.concurrent.TimeUnit;
  
  @State(Scope.Benchmark)
  @Fork(value = 1)
  @Warmup(iterations = 3)
  @Measurement(iterations = 10)
  @BenchmarkMode(Mode.AverageTime)
  @OutputTimeUnit(TimeUnit.MILLISECONDS)
  
  public class TimelineHashMapBenchmark {
      private static final int NUM_ENTRIES = 1_000_000;
  
      @Benchmark
      public Map<Integer, String> testAddEntriesInHashMap() {
          HashMap<Integer, String> map = new HashMap<>(NUM_ENTRIES);
          for (int i = 0; i < NUM_ENTRIES; i++) {
              int key = (int) (0xffffffff & ((i * 2862933555777941757L) + 3037000493L));
              map.put(key, String.valueOf(key));
          }
          return map;
      }
  
      @Benchmark
      public Map<Integer, String> testAddEntriesInTimelineMap() {
          SnapshotRegistry snapshotRegistry = new SnapshotRegistry(new LogContext());
          TimelineHashMap<Integer, String> map =
              new TimelineHashMap<>(snapshotRegistry, NUM_ENTRIES);
          for (int i = 0; i < NUM_ENTRIES; i++) {
              int key = (int) (0xffffffff & ((i * 2862933555777941757L) + 3037000493L));
              map.put(key, String.valueOf(key));
          }
          return map;
      }
  
      @Benchmark
      public Map<Integer, String> testAddEntriesWithSnapshots() {
          SnapshotRegistry snapshotRegistry = new SnapshotRegistry(new LogContext());
          TimelineHashMap<Integer, String> map =
              new TimelineHashMap<>(snapshotRegistry, NUM_ENTRIES);
          long epoch = 0;
          int j = 0;
          for (int i = 0; i < NUM_ENTRIES; i++) {
              int key = (int) (0xffffffff & ((i * 2862933555777941757L) + 3037000493L));
              if (j > 10 && key % 3 == 0) {
                  snapshotRegistry.deleteSnapshotsUpTo(epoch - 1000);
                  snapshotRegistry.idempotentCreateSnapshot(epoch);
                  j = 0;
              } else {
                  j++;
              }
              map.put(key, String.valueOf(key));
              epoch++;
          }
          return map;
      }
  }
  