From 35038df81d8f2af770d0916fe3e10126ad793019 Mon Sep 17 00:00:00 2001
From: Devaraj Das <ddas@apache.org>
Date: Fri, 19 Apr 2013 01:15:28 +0000
Subject: [PATCH] HBASE-7239. Introduces chunked reading for large cellblocks

git-svn-id: https://svn.apache.org/repos/asf/hbase/trunk@1469654 13f79535-47bb-0310-9956-ffa450edef68
---
 .../apache/hadoop/hbase/ipc/HBaseClient.java   |  2 +-
 .../org/apache/hadoop/hbase/ipc/IPCUtil.java   | 18 ++++++++++++++++++
 2 files changed, 19 insertions(+), 1 deletion(-)

diff --git a/hbase-client/src/main/java/org/apache/hadoop/hbase/ipc/HBaseClient.java b/hbase-client/src/main/java/org/apache/hadoop/hbase/ipc/HBaseClient.java
index 855e8dcc7a7..7fd037008a4 100644
--- a/hbase-client/src/main/java/org/apache/hadoop/hbase/ipc/HBaseClient.java
+++ b/hbase-client/src/main/java/org/apache/hadoop/hbase/ipc/HBaseClient.java
@@ -1026,7 +1026,7 @@ public class HBaseClient {
           if (responseHeader.hasCellBlockMeta()) {
             int size = responseHeader.getCellBlockMeta().getLength();
             byte [] cellBlock = new byte[size];
-            IOUtils.readFully(this.in, cellBlock, 0, cellBlock.length);
+            IPCUtil.readChunked(this.in, cellBlock, 0, size);
             cellBlockScanner = ipcUtil.createCellScanner(this.codec, this.compressor, cellBlock);
           }
           // it's possible that this call may have been cleaned up due to a RPC
diff --git a/hbase-client/src/main/java/org/apache/hadoop/hbase/ipc/IPCUtil.java b/hbase-client/src/main/java/org/apache/hadoop/hbase/ipc/IPCUtil.java
index 707c2bff05d..19c786d6b00 100644
--- a/hbase-client/src/main/java/org/apache/hadoop/hbase/ipc/IPCUtil.java
+++ b/hbase-client/src/main/java/org/apache/hadoop/hbase/ipc/IPCUtil.java
@@ -18,6 +18,7 @@
 package org.apache.hadoop.hbase.ipc;
 
 import java.io.ByteArrayInputStream;
+import java.io.DataInput;
 import java.io.DataInputStream;
 import java.io.IOException;
 import java.io.InputStream;
@@ -230,6 +231,23 @@ class IPCUtil {
     return bytes;
   }
 
+  /**
+   * Read in chunks of 8K (HBASE-7239)
+   * @param in
+   * @param dest
+   * @param offset
+   * @param len
+   * @throws IOException
+   */
+  static void readChunked(final DataInput in, byte[] dest, int offset, int len)
+      throws IOException {
+    int maxRead = 8192;
+
+    for (; offset < len; offset += maxRead) {
+      in.readFully(dest, offset, Math.min(len - offset, maxRead));
+    }
+  }
+
   /**
    * @param header
    * @param body