org.apache.hadoop.hbase.io

Interface HeapSize

All Known Subinterfaces:

Cacheable, Cell, ExtendedCell, FirstLevelBlockCache, RawCell, RegionSize, RegionSizeStore, SizedCellScanner

All Known Implementing Classes:

Append, BlockCacheKey, BucketCache, BufferedDataBlockEncoder.OffheapDecodedExtendedCell, BufferedDataBlockEncoder.OnheapDecodedCell, ByteBufferChunkKeyValue, ByteBufferExtendedCell, ByteBufferKeyOnlyKeyValue, ByteBufferKeyValue, CombinedBlockCache, Delete, EntryBuffers.RegionEntryBuffer, ExclusiveMemHFileBlock, HFileBlock, HFileBlockIndex.BlockIndexReader, HFileBlockIndex.ByteArrayKeyBlockIndexReader, HFileBlockIndex.CellBasedKeyBlockIndexReader, HFileContext, HMobStore, HRegion, HStore, InclusiveCombinedBlockCache, Increment, IndexOnlyLruBlockCache, IndividualBytesFieldCell, KeyOnlyFilter.KeyOnlyByteBufferExtendedCell, KeyOnlyFilter.KeyOnlyCell, KeyValue, KeyValue.KeyOnlyKeyValue, LruAdaptiveBlockCache, LruBlockCache, LruCachedBlock, LruCachedBlockQueue, MapReduceExtendedCell, Mutation, Mutation.CellWrapper, NoOpRegionSizeStore, NoTagByteBufferChunkKeyValue, NoTagsByteBufferKeyValue, NoTagsKeyValue, PrivateCellUtil.EmptyByteBufferExtendedCell, PrivateCellUtil.EmptyCell, PrivateCellUtil.FirstOnRowByteBufferExtendedCell, PrivateCellUtil.FirstOnRowCell, PrivateCellUtil.FirstOnRowColByteBufferExtendedCell, PrivateCellUtil.FirstOnRowColCell, PrivateCellUtil.FirstOnRowColTSByteBufferExtendedCell, PrivateCellUtil.FirstOnRowColTSCell, PrivateCellUtil.FirstOnRowDeleteFamilyCell, PrivateCellUtil.LastOnRowByteBufferExtendedCell, PrivateCellUtil.LastOnRowCell, PrivateCellUtil.LastOnRowColByteBufferExtendedCell, PrivateCellUtil.LastOnRowColCell, PrivateCellUtil.TagRewriteByteBufferExtendedCell, PrivateCellUtil.TagRewriteCell, PrivateCellUtil.ValueAndTagRewriteByteBufferExtendedCell, PrivateCellUtil.ValueAndTagRewriteCell, Put, RegionSizeImpl, RegionSizeStoreImpl, SharedMemHFileBlock, SizeCachedByteBufferKeyValue, SizeCachedKeyValue, SizeCachedNoTagsByteBufferKeyValue, SizeCachedNoTagsKeyValue, StoreContext, TinyLfuBlockCache, WALEdit

@InterfaceAudience.Private
public interface HeapSize

Implementations can be asked for an estimate of their size in bytes.

Useful for sizing caches. Its a given that implementation approximations do not account for 32 vs 64 bit nor for different VM implementations.

An Object's size is determined by the non-static data members in it, as well as the fixed Object overhead.

For example:

 public class SampleObject implements HeapSize {

   int[] numbers;
   int x;
 }
 

Method Summary

Modifier and Type	Method and Description
long	heapSize() Return the approximate 'exclusive deep size' of implementing object.

Method Detail

heapSize

long heapSize()

Return the approximate 'exclusive deep size' of implementing object. Includes count of payload and hosting object sizings.