[
https://issues.apache.org/jira/browse/HBASE-4218?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
Zhihong Yu updated HBASE-4218:
------------------------------
Comment: was deleted
(was: Integrated in HBase-TRUNK-security #48 (See
[https://builds.apache.org/job/HBase-TRUNK-security/48/])
HBASE-4218 Data Block Encoding of KeyValues - revert, problems were
uncovered during cluster testing
tedyu :
Files :
* /hbase/trunk/src/main/java/org/apache/hadoop/hbase/HColumnDescriptor.java
* /hbase/trunk/src/main/java/org/apache/hadoop/hbase/KeyValue.java
* /hbase/trunk/src/main/java/org/apache/hadoop/hbase/io/HalfStoreFileReader.java
*
/hbase/trunk/src/main/java/org/apache/hadoop/hbase/io/encoding/BitsetKeyDeltaEncoder.java
*
/hbase/trunk/src/main/java/org/apache/hadoop/hbase/io/encoding/BufferedDataBlockEncoder.java
*
/hbase/trunk/src/main/java/org/apache/hadoop/hbase/io/encoding/CompressionState.java
*
/hbase/trunk/src/main/java/org/apache/hadoop/hbase/io/encoding/CopyKeyDataBlockEncoder.java
*
/hbase/trunk/src/main/java/org/apache/hadoop/hbase/io/encoding/DataBlockEncoder.java
*
/hbase/trunk/src/main/java/org/apache/hadoop/hbase/io/encoding/DataBlockEncodings.java
*
/hbase/trunk/src/main/java/org/apache/hadoop/hbase/io/encoding/DiffKeyDeltaEncoder.java
*
/hbase/trunk/src/main/java/org/apache/hadoop/hbase/io/encoding/EncodedDataBlock.java
*
/hbase/trunk/src/main/java/org/apache/hadoop/hbase/io/encoding/EncoderBufferTooSmallException.java
*
/hbase/trunk/src/main/java/org/apache/hadoop/hbase/io/encoding/FastDiffDeltaEncoder.java
*
/hbase/trunk/src/main/java/org/apache/hadoop/hbase/io/encoding/PrefixKeyDeltaEncoder.java
*
/hbase/trunk/src/main/java/org/apache/hadoop/hbase/io/hfile/AbstractHFileReader.java
*
/hbase/trunk/src/main/java/org/apache/hadoop/hbase/io/hfile/AbstractHFileWriter.java
* /hbase/trunk/src/main/java/org/apache/hadoop/hbase/io/hfile/BlockType.java
* /hbase/trunk/src/main/java/org/apache/hadoop/hbase/io/hfile/HFile.java
* /hbase/trunk/src/main/java/org/apache/hadoop/hbase/io/hfile/HFileBlock.java
*
/hbase/trunk/src/main/java/org/apache/hadoop/hbase/io/hfile/HFileBlockIndex.java
*
/hbase/trunk/src/main/java/org/apache/hadoop/hbase/io/hfile/HFileDataBlockEncoder.java
*
/hbase/trunk/src/main/java/org/apache/hadoop/hbase/io/hfile/HFileDataBlockEncoderImpl.java
*
/hbase/trunk/src/main/java/org/apache/hadoop/hbase/io/hfile/HFilePrettyPrinter.java
* /hbase/trunk/src/main/java/org/apache/hadoop/hbase/io/hfile/HFileReaderV1.java
* /hbase/trunk/src/main/java/org/apache/hadoop/hbase/io/hfile/HFileReaderV2.java
* /hbase/trunk/src/main/java/org/apache/hadoop/hbase/io/hfile/HFileWriterV1.java
* /hbase/trunk/src/main/java/org/apache/hadoop/hbase/io/hfile/HFileWriterV2.java
* /hbase/trunk/src/main/java/org/apache/hadoop/hbase/io/hfile/LruBlockCache.java
*
/hbase/trunk/src/main/java/org/apache/hadoop/hbase/io/hfile/NoOpDataBlockEncoder.java
*
/hbase/trunk/src/main/java/org/apache/hadoop/hbase/mapreduce/LoadIncrementalHFiles.java
* /hbase/trunk/src/main/java/org/apache/hadoop/hbase/regionserver/MemStore.java
* /hbase/trunk/src/main/java/org/apache/hadoop/hbase/regionserver/Store.java
* /hbase/trunk/src/main/java/org/apache/hadoop/hbase/regionserver/StoreFile.java
*
/hbase/trunk/src/main/java/org/apache/hadoop/hbase/regionserver/StoreFileScanner.java
*
/hbase/trunk/src/main/java/org/apache/hadoop/hbase/regionserver/metrics/SchemaConfigured.java
* /hbase/trunk/src/main/java/org/apache/hadoop/hbase/util/ByteBufferUtils.java
* /hbase/trunk/src/main/ruby/hbase/admin.rb
* /hbase/trunk/src/test/java/org/apache/hadoop/hbase/HBaseTestCase.java
*
/hbase/trunk/src/test/java/org/apache/hadoop/hbase/HFilePerformanceEvaluation.java
*
/hbase/trunk/src/test/java/org/apache/hadoop/hbase/client/TestFromClientSide.java
*
/hbase/trunk/src/test/java/org/apache/hadoop/hbase/io/TestHalfStoreFileReader.java
* /hbase/trunk/src/test/java/org/apache/hadoop/hbase/io/TestHeapSize.java
*
/hbase/trunk/src/test/java/org/apache/hadoop/hbase/io/encoding/RedundantKVGenerator.java
*
/hbase/trunk/src/test/java/org/apache/hadoop/hbase/io/encoding/TestBufferedDataBlockEncoder.java
*
/hbase/trunk/src/test/java/org/apache/hadoop/hbase/io/encoding/TestDataBlockEncoders.java
*
/hbase/trunk/src/test/java/org/apache/hadoop/hbase/io/hfile/CacheTestUtils.java
*
/hbase/trunk/src/test/java/org/apache/hadoop/hbase/io/hfile/TestCacheOnWrite.java
*
/hbase/trunk/src/test/java/org/apache/hadoop/hbase/io/hfile/TestHFileBlock.java
*
/hbase/trunk/src/test/java/org/apache/hadoop/hbase/io/hfile/TestHFileBlockIndex.java
*
/hbase/trunk/src/test/java/org/apache/hadoop/hbase/io/hfile/TestHFileDataBlockEncoder.java
*
/hbase/trunk/src/test/java/org/apache/hadoop/hbase/io/hfile/TestHFileWriterV2.java
*
/hbase/trunk/src/test/java/org/apache/hadoop/hbase/mapreduce/TestImportExport.java
*
/hbase/trunk/src/test/java/org/apache/hadoop/hbase/regionserver/CreateRandomStoreFile.java
*
/hbase/trunk/src/test/java/org/apache/hadoop/hbase/regionserver/DataBlockEncodingTool.java
*
/hbase/trunk/src/test/java/org/apache/hadoop/hbase/regionserver/EncodedSeekPerformanceTest.java
*
/hbase/trunk/src/test/java/org/apache/hadoop/hbase/regionserver/TestCompactSelection.java
*
/hbase/trunk/src/test/java/org/apache/hadoop/hbase/regionserver/TestCompaction.java
*
/hbase/trunk/src/test/java/org/apache/hadoop/hbase/regionserver/TestCompoundBloomFilter.java
*
/hbase/trunk/src/test/java/org/apache/hadoop/hbase/regionserver/TestFSErrorsExposed.java
*
/hbase/trunk/src/test/java/org/apache/hadoop/hbase/regionserver/TestStoreFile.java
* /hbase/trunk/src/test/java/org/apache/hadoop/hbase/util/LoadTestTool.java
*
/hbase/trunk/src/test/java/org/apache/hadoop/hbase/util/TestByteBufferUtils.java
)
> Data Block Encoding of KeyValues (aka delta encoding / prefix compression)
> ---------------------------------------------------------------------------
>
> Key: HBASE-4218
> URL: https://issues.apache.org/jira/browse/HBASE-4218
> Project: HBase
> Issue Type: Improvement
> Components: io
> Affects Versions: 0.94.0
> Reporter: Jacek Migdal
> Assignee: Mikhail Bautin
> Labels: compression
> Fix For: 0.94.0
>
> Attachments: 0001-Delta-encoding-fixed-encoded-scanners.patch,
> 0001-Delta-encoding.patch, D447.1.patch, D447.10.patch, D447.11.patch,
> D447.12.patch, D447.13.patch, D447.2.patch, D447.3.patch, D447.4.patch,
> D447.5.patch, D447.6.patch, D447.7.patch, D447.8.patch, D447.9.patch,
> Data-block-encoding-2011-12-23.patch,
> Delta-encoding.patch-2011-12-22_11_52_07.patch,
> Delta_encoding_with_memstore_TS.patch, open-source.diff
>
>
> A compression for keys. Keys are sorted in HFile and they are usually very
> similar. Because of that, it is possible to design better compression than
> general purpose algorithms,
> It is an additional step designed to be used in memory. It aims to save
> memory in cache as well as speeding seeks within HFileBlocks. It should
> improve performance a lot, if key lengths are larger than value lengths. For
> example, it makes a lot of sense to use it when value is a counter.
> Initial tests on real data (key length = ~ 90 bytes , value length = 8 bytes)
> shows that I could achieve decent level of compression:
> key compression ratio: 92%
> total compression ratio: 85%
> LZO on the same data: 85%
> LZO after delta encoding: 91%
> While having much better performance (20-80% faster decompression ratio than
> LZO). Moreover, it should allow far more efficient seeking which should
> improve performance a bit.
> It seems that a simple compression algorithms are good enough. Most of the
> savings are due to prefix compression, int128 encoding, timestamp diffs and
> bitfields to avoid duplication. That way, comparisons of compressed data can
> be much faster than a byte comparator (thanks to prefix compression and
> bitfields).
> In order to implement it in HBase two important changes in design will be
> needed:
> -solidify interface to HFileBlock / HFileReader Scanner to provide seeking
> and iterating; access to uncompressed buffer in HFileBlock will have bad
> performance
> -extend comparators to support comparison assuming that N first bytes are
> equal (or some fields are equal)
> Link to a discussion about something similar:
> http://search-hadoop.com/m/5aqGXJEnaD1/hbase+windows&subj=Re+prefix+compression
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