HBASE-16502 Reduce garbage in BufferedDataBlockEncoder (binlijin)

hbase-common/src/main/java/org/apache/hadoop/hbase/io/encoding/BufferedDataBlockEncoder.java

@@ -95,12 +95,20 @@ abstract class BufferedDataBlockEncoder implements DataBlockEncoder {
 
     /** We need to store a copy of the key. */
     protected byte[] keyBuffer = new byte[INITIAL_KEY_BUFFER_SIZE];
-    protected byte[] tagsBuffer = new byte[INITIAL_KEY_BUFFER_SIZE];
+    protected byte[] tagsBuffer = null;
 
     protected long memstoreTS;
     protected int nextKvOffset;
     protected KeyValue.KeyOnlyKeyValue currentKey = new KeyValue.KeyOnlyKeyValue();
 
+    public SeekerState(boolean tagsCompressed) {
+      if (tagsCompressed) {
+        tagsBuffer = new byte[INITIAL_KEY_BUFFER_SIZE];
+      } else {
+        tagsBuffer = HConstants.EMPTY_BYTE_ARRAY;
+      }
+    }
+
     protected boolean isValid() {
       return valueOffset != -1;
     }
@@ -527,8 +535,7 @@ abstract class BufferedDataBlockEncoder implements DataBlockEncoder {
     protected final KVComparator comparator;
     protected final SamePrefixComparator<byte[]> samePrefixComparator;
     protected ByteBuffer currentBuffer;
-    protected STATE current = createSeekerState(); // always valid
+    protected STATE current, previous;
-    protected STATE previous = createSeekerState(); // may not be valid
     protected TagCompressionContext tagCompressionContext = null;
 
     public BufferedEncodedSeeker(KVComparator comparator,
@@ -543,6 +550,8 @@ abstract class BufferedDataBlockEncoder implements DataBlockEncoder {
           throw new RuntimeException("Failed to initialize TagCompressionContext", e);
         }
       }
+      current = createSeekerState(); // always valid
+      previous = createSeekerState(); // may not be valid
     }
     
     protected boolean includesMvcc() {
@@ -553,6 +562,10 @@ abstract class BufferedDataBlockEncoder implements DataBlockEncoder {
       return this.decodingCtx.getHFileContext().isIncludesTags();
     }
 
+    protected boolean tagsCompressed() {
+      return this.decodingCtx.getHFileContext().isCompressTags();
+    }
+
     @Override
     public int compareKey(KVComparator comparator, byte[] key, int offset, int length) {
       return comparator.compareFlatKey(key, offset, length,
@@ -805,7 +818,7 @@ abstract class BufferedDataBlockEncoder implements DataBlockEncoder {
     protected STATE createSeekerState() {
       // This will fail for non-default seeker state if the subclass does not
       // override this method.
-      return (STATE) new SeekerState();
+      return (STATE) new SeekerState(this.tagsCompressed());
     }
 
     abstract protected void decodeFirst();

hbase-common/src/main/java/org/apache/hadoop/hbase/io/encoding/DiffKeyDeltaEncoder.java

@@ -21,12 +21,12 @@ import java.io.DataOutputStream;
 import java.io.IOException;
 import java.nio.ByteBuffer;
 
-import org.apache.hadoop.hbase.classification.InterfaceAudience;
 import org.apache.hadoop.hbase.Cell;
 import org.apache.hadoop.hbase.CellUtil;
 import org.apache.hadoop.hbase.KeyValue;
-import org.apache.hadoop.hbase.KeyValueUtil;
 import org.apache.hadoop.hbase.KeyValue.KVComparator;
+import org.apache.hadoop.hbase.KeyValueUtil;
+import org.apache.hadoop.hbase.classification.InterfaceAudience;
 import org.apache.hadoop.hbase.util.ByteBufferUtils;
 import org.apache.hadoop.hbase.util.Bytes;
 
@@ -362,6 +362,10 @@ public class DiffKeyDeltaEncoder extends BufferedDataBlockEncoder {
     private int rowLengthWithSize;
     private long timestamp;
 
+    public DiffSeekerState(boolean tagsCompressed) {
+      super(tagsCompressed);
+    }
+
     @Override
     protected void copyFromNext(SeekerState that) {
       super.copyFromNext(that);
@@ -497,7 +501,7 @@ public class DiffKeyDeltaEncoder extends BufferedDataBlockEncoder {
 
       @Override
       protected DiffSeekerState createSeekerState() {
-        return new DiffSeekerState();
+        return new DiffSeekerState(this.tagsCompressed());
       }
     };
   }

hbase-common/src/main/java/org/apache/hadoop/hbase/io/encoding/FastDiffDeltaEncoder.java

@@ -21,12 +21,12 @@ import java.io.DataOutputStream;
 import java.io.IOException;
 import java.nio.ByteBuffer;
 
-import org.apache.hadoop.hbase.classification.InterfaceAudience;
 import org.apache.hadoop.hbase.Cell;
 import org.apache.hadoop.hbase.CellUtil;
 import org.apache.hadoop.hbase.KeyValue;
-import org.apache.hadoop.hbase.KeyValueUtil;
 import org.apache.hadoop.hbase.KeyValue.KVComparator;
+import org.apache.hadoop.hbase.KeyValueUtil;
+import org.apache.hadoop.hbase.classification.InterfaceAudience;
 import org.apache.hadoop.hbase.util.ByteBufferUtils;
 import org.apache.hadoop.hbase.util.Bytes;
 
@@ -379,6 +379,10 @@ public class FastDiffDeltaEncoder extends BufferedDataBlockEncoder {
     private int rowLengthWithSize;
     private int familyLengthWithSize;
 
+    public FastDiffSeekerState(boolean tagsCompressed) {
+      super(tagsCompressed);
+    }
+
     @Override
     protected void copyFromNext(SeekerState that) {
       super.copyFromNext(that);
@@ -518,7 +522,7 @@ public class FastDiffDeltaEncoder extends BufferedDataBlockEncoder {
 
       @Override
       protected FastDiffSeekerState createSeekerState() {
-        return new FastDiffSeekerState();
+        return new FastDiffSeekerState(this.tagsCompressed());
       }
     };
   }

hbase-server/src/test/java/org/apache/hadoop/hbase/io/encoding/TestBufferedDataBlockEncoder.java

@@ -27,8 +27,8 @@ public class TestBufferedDataBlockEncoder {
 
   @Test
   public void testEnsureSpaceForKey() {
-    BufferedDataBlockEncoder.SeekerState state =
+    BufferedDataBlockEncoder.SeekerState state = new BufferedDataBlockEncoder.SeekerState(
-        new BufferedDataBlockEncoder.SeekerState();
+        false);
     for (int i = 1; i <= 65536; ++i) {
       state.keyLength = i;
       state.ensureSpaceForKey();