diff --git a/hbase-common/src/main/java/org/apache/hadoop/hbase/HConstants.java b/hbase-common/src/main/java/org/apache/hadoop/hbase/HConstants.java
index 58c7d4ce46f..437fb137bbd 100644
--- a/hbase-common/src/main/java/org/apache/hadoop/hbase/HConstants.java
+++ b/hbase-common/src/main/java/org/apache/hadoop/hbase/HConstants.java
@@ -548,6 +548,16 @@ public final class HConstants {
    */
   public static int DEFAULT_HBASE_CLIENT_PREFETCH_LIMIT = 10;
 
+  /**
+   * Parameter name to set the default scanner caching for all clients.
+   */
+  public static String HBASE_CLIENT_SCANNER_CACHING = "hbase.client.scanner.caching";
+
+  /**
+   * Default value for {@link #HBASE_CLIENT_SCANNER_CACHING}
+   */
+  public static int DEFAULT_HBASE_CLIENT_SCANNER_CACHING = 100;
+
   /**
    * Parameter name for number of rows that will be fetched when calling next on
    * a scanner if it is not served from memory. Higher caching values will
diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/client/ClientScanner.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/client/ClientScanner.java
index 0f1a3aa83f2..18091b57f2d 100644
--- a/hbase-server/src/main/java/org/apache/hadoop/hbase/client/ClientScanner.java
+++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/client/ClientScanner.java
@@ -121,7 +121,9 @@ public class ClientScanner extends AbstractClientScanner {
       if (this.scan.getCaching() > 0) {
         this.caching = this.scan.getCaching();
       } else {
-        this.caching = conf.getInt("hbase.client.scanner.caching", 1);
+        this.caching = conf.getInt(
+            HConstants.HBASE_CLIENT_SCANNER_CACHING,
+            HConstants.DEFAULT_HBASE_CLIENT_SCANNER_CACHING);
       }
 
       // initialize the scanner
diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/client/HTable.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/client/HTable.java
index 1c5bf7d8901..373a76613c8 100644
--- a/hbase-server/src/main/java/org/apache/hadoop/hbase/client/HTable.java
+++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/client/HTable.java
@@ -258,7 +258,8 @@ public class HTable implements HTableInterface {
     this.autoFlush = true;
     this.currentWriteBufferSize = 0;
     this.scannerCaching = this.configuration.getInt(
-        "hbase.client.scanner.caching", 1);
+        HConstants.HBASE_CLIENT_SCANNER_CACHING,
+        HConstants.DEFAULT_HBASE_CLIENT_SCANNER_CACHING);
 
     this.maxKeyValueSize = this.configuration.getInt(
         "hbase.client.keyvalue.maxsize", -1);
diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/HBaseClient.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/HBaseClient.java
index a7ec5b53039..33786b70816 100644
--- a/hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/HBaseClient.java
+++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/HBaseClient.java
@@ -1157,7 +1157,7 @@ public class HBaseClient {
       conf.getInt("hbase.ipc.client.connection.maxidletime", 10000); //10s
     this.maxRetries = conf.getInt("hbase.ipc.client.connect.max.retries", 0);
     this.failureSleep = conf.getInt("hbase.client.pause", 1000);
-    this.tcpNoDelay = conf.getBoolean("hbase.ipc.client.tcpnodelay", false);
+    this.tcpNoDelay = conf.getBoolean("hbase.ipc.client.tcpnodelay", true);
     this.tcpKeepAlive = conf.getBoolean("hbase.ipc.client.tcpkeepalive", true);
     this.pingInterval = getPingInterval(conf);
     if (LOG.isDebugEnabled()) {
diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/HBaseServer.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/HBaseServer.java
index eba668ad8dd..1c9736c77cf 100644
--- a/hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/HBaseServer.java
+++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/HBaseServer.java
@@ -1938,7 +1938,7 @@ public abstract class HBaseServer implements RpcServer {
     this.port = listener.getAddress().getPort();
     this.rpcMetrics = new HBaseRpcMetrics(
         serverName, Integer.toString(this.port));
-    this.tcpNoDelay = conf.getBoolean("ipc.server.tcpnodelay", false);
+    this.tcpNoDelay = conf.getBoolean("ipc.server.tcpnodelay", true);
     this.tcpKeepAlive = conf.getBoolean("ipc.server.tcpkeepalive", true);
 
     this.warnDelayedCalls = conf.getInt(WARN_DELAYED_CALLS,
diff --git a/hbase-server/src/main/resources/hbase-default.xml b/hbase-server/src/main/resources/hbase-default.xml
index a986ceefad0..08e35e31d7e 100644
--- a/hbase-server/src/main/resources/hbase-default.xml
+++ b/hbase-server/src/main/resources/hbase-default.xml
@@ -133,7 +133,7 @@
   </property>
   <property>
     <name>hbase.client.scanner.caching</name>
-    <value>1</value>
+    <value>100</value>
     <description>Number of rows that will be fetched when calling next
     on a scanner if it is not served from (local, client) memory. Higher
     caching values will enable faster scanners but will eat up more memory
@@ -528,6 +528,13 @@
     used for client / server RPC call marshalling.
     </description>
   </property>
+  <property>
+    <name>hbase.ipc.client.tcpnodelay</name>
+    <value>true</value>
+    <description>Set no delay on rpc socket connections.  See
+    http://docs.oracle.com/javase/1.5.0/docs/api/java/net/Socket.html#getTcpNoDelay()
+    </description>
+  </property>
 
   <!-- The following properties configure authentication information for
        HBase processes when using Kerberos security.  There are no default
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/client/TestFromClientSide.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/client/TestFromClientSide.java
index df7eb2b4e40..8e48cb54129 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/client/TestFromClientSide.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/client/TestFromClientSide.java
@@ -4663,7 +4663,20 @@ public class TestFromClientSide {
     // turn on scan metrics
     Scan scan = new Scan();
     scan.setAttribute(Scan.SCAN_ATTRIBUTES_METRICS_ENABLE, Bytes.toBytes(Boolean.TRUE));
+    scan.setCaching(numRecords+1);
     ResultScanner scanner = ht.getScanner(scan);
+    for (Result result : scanner.next(numRecords - 1)) {
+    }
+    scanner.close();
+    // need to have at one next roundtrip in order to collect metrics
+    // here we have less than <numRecord>+1 KVs, so no metrics were collected
+    assertNull(scan.getAttribute(Scan.SCAN_ATTRIBUTES_METRICS_DATA));
+
+    // set caching to 1, becasue metrics are collected in each roundtrip only
+    scan = new Scan();
+    scan.setAttribute(Scan.SCAN_ATTRIBUTES_METRICS_ENABLE, Bytes.toBytes(Boolean.TRUE));
+    scan.setCaching(1);
+    scanner = ht.getScanner(scan);
     // per HBASE-5717, this should still collect even if you don't run all the way to
     // the end of the scanner. So this is asking for 2 of the 3 rows we inserted.
     for (Result result : scanner.next(numRecords - 1)) {
@@ -4677,6 +4690,7 @@ public class TestFromClientSide {
     // now, test that the metrics are still collected even if you don't call close, but do
     // run past the end of all the records
     Scan scanWithoutClose = new Scan();
+    scanWithoutClose.setCaching(1);
     scanWithoutClose.setAttribute(Scan.SCAN_ATTRIBUTES_METRICS_ENABLE, Bytes.toBytes(Boolean.TRUE));
     ResultScanner scannerWithoutClose = ht.getScanner(scanWithoutClose);
     for (Result result : scannerWithoutClose.next(numRecords + 1)) {
@@ -4688,6 +4702,8 @@ public class TestFromClientSide {
     // finally, test that the metrics are collected correctly if you both run past all the records,
     // AND close the scanner
     Scan scanWithClose = new Scan();
+    // make sure we can set caching up to the number of a scanned values
+    scanWithClose.setCaching(numRecords);
     scanWithClose.setAttribute(Scan.SCAN_ATTRIBUTES_METRICS_ENABLE, Bytes.toBytes(Boolean.TRUE));
     ResultScanner scannerWithClose = ht.getScanner(scanWithClose);
     for (Result result : scannerWithClose.next(numRecords + 1)) {
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/client/TestScannerTimeout.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/client/TestScannerTimeout.java
index f084080c505..7b6f86abd4b 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/client/TestScannerTimeout.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/client/TestScannerTimeout.java
@@ -98,6 +98,7 @@ public class TestScannerTimeout {
   public void test2481() throws Exception {
     LOG.info("START ************ test2481");
     Scan scan = new Scan();
+    scan.setCaching(1);
     HTable table =
       new HTable(new Configuration(TEST_UTIL.getConfiguration()), TABLE_NAME);
     ResultScanner r = table.getScanner(scan);