[HBASE-11234] FastDiffDeltaEncoder#getFirstKeyInBlock returns wrong result

• Type: Bug
• Status: Closed
• Priority: Critical
• Resolution: Fixed
• Fix Version/s: 0.99.0, 0.96.3, 0.98.3, 0.94.21
• Hadoop Flags: Reviewed
• Assignee: Chunhui Shen
• Reporter: Chunhui Shen
• Created: 22/May/14 08:48
• Updated: 11/Jul/14 06:26
• Resolved: 27/May/14 14:52

Description

As Ted found,

With this change:

Index: hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestReversibleScanners.java
===================================================================
--- hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestReversibleScanners.java	(revision 1596579)
+++ hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestReversibleScanners.java	(working copy)
@@ -51,6 +51,7 @@
 import org.apache.hadoop.hbase.filter.FilterList.Operator;
 import org.apache.hadoop.hbase.filter.PageFilter;
 import org.apache.hadoop.hbase.filter.SingleColumnValueFilter;
+import org.apache.hadoop.hbase.io.encoding.DataBlockEncoding;
 import org.apache.hadoop.hbase.io.hfile.CacheConfig;
 import org.apache.hadoop.hbase.io.hfile.HFileContext;
 import org.apache.hadoop.hbase.io.hfile.HFileContextBuilder;
@@ -90,6 +91,7 @@
     CacheConfig cacheConf = new CacheConfig(TEST_UTIL.getConfiguration());
     HFileContextBuilder hcBuilder = new HFileContextBuilder();
     hcBuilder.withBlockSize(2 * 1024);
+    hcBuilder.withDataBlockEncoding(DataBlockEncoding.FAST_DIFF);
     HFileContext hFileContext = hcBuilder.build();
     StoreFile.Writer writer = new StoreFile.WriterBuilder(
         TEST_UTIL.getConfiguration(), cacheConf, fs).withOutputDir(

I got:

java.lang.AssertionError: expected:<testRow0197/testCf:testQual0000/1400712260004/Put/vlen=13/mvcc=5> but was:<testRow0198/testCf:testQual0000/1400712260004/ Put/vlen=13/mvcc=0>
at org.junit.Assert.fail(Assert.java:88)
at org.junit.Assert.failNotEquals(Assert.java:743)
at org.junit.Assert.assertEquals(Assert.java:118)
at org.junit.Assert.assertEquals(Assert.java:144)
at org.apache.hadoop.hbase.regionserver.TestReversibleScanners.seekTestOfReversibleKeyValueScanner(TestReversibleScanners.java:533)
at org.apache.hadoop.hbase.regionserver.TestReversibleScanners.testReversibleStoreFileScanner(TestReversibleScanners.java:108)

After debugging, it seems the method of FastDiffDeltaEncoder#getFirstKeyInBlock become broken. And it will cause hfilescanner#seekBefore returns wrong result.

The solution is simple, see the patch.

Issue Links

• relates to: HBASE-11246 Backport HBASE-11234 'FastDiffDeltaEncoder#getFirstKeyInBlock returns wrong result'