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1   /**
2    *
3    * Licensed to the Apache Software Foundation (ASF) under one
4    * or more contributor license agreements.  See the NOTICE file
5    * distributed with this work for additional information
6    * regarding copyright ownership.  The ASF licenses this file
7    * to you under the Apache License, Version 2.0 (the
8    * "License"); you may not use this file except in compliance
9    * with the License.  You may obtain a copy of the License at
10   *
11   *     http://www.apache.org/licenses/LICENSE-2.0
12   *
13   * Unless required by applicable law or agreed to in writing, software
14   * distributed under the License is distributed on an "AS IS" BASIS,
15   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
16   * See the License for the specific language governing permissions and
17   * limitations under the License.
18   */
19  
20  package org.apache.hadoop.hbase.regionserver.wal;
21  
22  import com.google.common.annotations.VisibleForTesting;
23  import org.apache.commons.logging.Log;
24  import org.apache.commons.logging.LogFactory;
25  import org.apache.hadoop.hbase.classification.InterfaceAudience;
26  import org.apache.hadoop.hbase.CompatibilitySingletonFactory;
27  import org.apache.hadoop.util.StringUtils;
28  
29  /**
30   * Class used to push numbers about the WAL into the metrics subsystem.  This will take a
31   * single function call and turn it into multiple manipulations of the hadoop metrics system.
32   */
33  @InterfaceAudience.Private
34  public class MetricsWAL extends WALActionsListener.Base {
35    private static final Log LOG = LogFactory.getLog(MetricsWAL.class);
36  
37    private final MetricsWALSource source;
38  
39    public MetricsWAL() {
40      this(CompatibilitySingletonFactory.getInstance(MetricsWALSource.class));
41    }
42  
43    @VisibleForTesting
44    MetricsWAL(MetricsWALSource s) {
45      this.source = s;
46    }
47  
48    @Override
49    public void postSync(final long timeInNanos, final int handlerSyncs) {
50      source.incrementSyncTime(timeInNanos/1000000L);
51    }
52  
53    @Override
54    public void postAppend(final long size, final long time) {
55      source.incrementAppendCount();
56      source.incrementAppendTime(time);
57      source.incrementAppendSize(size);
58  
59      if (time > 1000) {
60        source.incrementSlowAppendCount();
61        LOG.warn(String.format("%s took %d ms appending an edit to wal; len~=%s",
62            Thread.currentThread().getName(),
63            time,
64            StringUtils.humanReadableInt(size)));
65      }
66    }
67  
68    @Override
69    public void logRollRequested(boolean underReplicated) {
70      source.incrementLogRollRequested();
71      if (underReplicated) {
72        source.incrementLowReplicationLogRoll();
73      }
74    }
75  }