From 5d2708f628d4718f6267e9da6c8cbafeda66f4fb Mon Sep 17 00:00:00 2001
From: anoopsjohn <anoopsamjohn@gmail.com>
Date: Thu, 6 Aug 2015 10:16:51 +0530
Subject: [PATCH] HBASE-14186 Read mvcc vlong optimization.

---
 .../hadoop/hbase/io/hfile/HFileReaderImpl.java    | 15 ++++++++++++++-
 1 file changed, 14 insertions(+), 1 deletion(-)

diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/io/hfile/HFileReaderImpl.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/io/hfile/HFileReaderImpl.java
index 82f5366496f..18240b1c7d6 100644
--- a/hbase-server/src/main/java/org/apache/hadoop/hbase/io/hfile/HFileReaderImpl.java
+++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/io/hfile/HFileReaderImpl.java
@@ -633,9 +633,22 @@ public class HFileReaderImpl implements HFile.Reader, Configurable {
       if (len == 1) {
         this.currMemstoreTS = firstByte;
       } else {
+        int remaining = len -1;
         long i = 0;
         offsetFromPos++;
-        for (int idx = 0; idx < len - 1; idx++) {
+        if (remaining >= Bytes.SIZEOF_INT) {
+          i = blockBuffer.getIntAfterPosition(offsetFromPos);
+          remaining -= Bytes.SIZEOF_INT;
+          offsetFromPos += Bytes.SIZEOF_INT;
+        }
+        if (remaining >= Bytes.SIZEOF_SHORT) {
+          short s = blockBuffer.getShortAfterPosition(offsetFromPos);
+          i = i << 16;
+          i = i | (s & 0xFFFF);
+          remaining -= Bytes.SIZEOF_SHORT;
+          offsetFromPos += Bytes.SIZEOF_SHORT;
+        }
+        for (int idx = 0; idx < remaining; idx++) {
           byte b = blockBuffer.getByteAfterPosition(offsetFromPos + idx);
           i = i << 8;
           i = i | (b & 0xFF);