hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/CSLMImmutableSegment.java

   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 package org.apache.hadoop.hbase.regionserver;
  20
  21 import org.apache.yetus.audience.InterfaceAudience;
  22 import org.apache.hadoop.hbase.util.ClassSize;
  23
  24 /**
  25  * CSLMImmutableSegment is an abstract class that extends the API supported by a {@link Segment},
  26  * and {@link ImmutableSegment}. This immutable segment is working with CellSet with
  27  * ConcurrentSkipListMap (CSLM) delegatee.
  28  */
  29 @InterfaceAudience.Private
  30 public class CSLMImmutableSegment extends ImmutableSegment {
  31   public static final long DEEP_OVERHEAD_CSLM =
  32       ImmutableSegment.DEEP_OVERHEAD + ClassSize.CONCURRENT_SKIPLISTMAP;
  33
  34   /**------------------------------------------------------------------------
  35    * Copy C-tor to be used when new CSLMImmutableSegment is being built from a Mutable one.
  36    * This C-tor should be used when active MutableSegment is pushed into the compaction
  37    * pipeline and becomes an ImmutableSegment.
  38    */
  39   protected CSLMImmutableSegment(Segment segment, MemStoreSizing memstoreSizing) {
  40     super(segment);
  41     // update the segment metadata heap size
  42     long indexOverhead = -MutableSegment.DEEP_OVERHEAD + DEEP_OVERHEAD_CSLM;
  43     incMemStoreSize(0, indexOverhead, 0, 0); // CSLM is always on-heap
  44     if (memstoreSizing != null) {
  45       memstoreSizing.incMemStoreSize(0, indexOverhead, 0, 0);
  46     }
  47   }
  48
  49   @Override
  50   protected long indexEntrySize() {
  51     return ClassSize.CONCURRENT_SKIPLISTMAP_ENTRY;
  52   }
  53
  54   @Override protected boolean canBeFlattened() {
  55     return true;
  56   }
  57 }