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.cassandra.db.commitlog;
  
  import java.util.concurrent.TimeUnit;
  
  import org.apache.cassandra.config.DatabaseDescriptor;
  
  import static org.apache.cassandra.utils.Clock.Global.nanoTime;
  
  class PeriodicCommitLogService extends AbstractCommitLogService
  {
      private static final long blockWhenSyncLagsNanos = TimeUnit.MILLISECONDS.toNanos(DatabaseDescriptor.getPeriodicCommitLogSyncBlock());
  
      public PeriodicCommitLogService(final CommitLog commitLog)
      {
          super(commitLog, "PERIODIC-COMMIT-LOG-SYNCER", DatabaseDescriptor.getCommitLogSyncPeriod(),
                !(commitLog.configuration.useCompression() || commitLog.configuration.useEncryption()));
      }
  
      protected void maybeWaitForSync(CommitLogSegment.Allocation alloc)
      {
          long expectedSyncTime = nanoTime() - blockWhenSyncLagsNanos;
          if (lastSyncedAt < expectedSyncTime)
          {
              pending.incrementAndGet();
              awaitSyncAt(expectedSyncTime, commitLog.metrics.waitingOnCommit.time());
              pending.decrementAndGet();
          }
      }
  }
  