From a8dee7c237adfcf842232a218d6436e60b077708 Mon Sep 17 00:00:00 2001
From: Suresh Srinivas <suresh@apache.org>
Date: Thu, 28 Feb 2013 22:08:26 +0000
Subject: [PATCH] HDFS-4518. Merge 1451348 from trunk.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1451387 13f79535-47bb-0310-9956-ffa450edef68
---
 hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt   |  3 +++
 .../hdfs/server/namenode/FSNamesystem.java    | 27 ++++++++++++-------
 .../namenode/metrics/TestNameNodeMetrics.java | 20 +++++++++++++-
 3 files changed, 39 insertions(+), 11 deletions(-)

diff --git a/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt b/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt
index 7ea1bc1ba49..4bcb68a97c4 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt
+++ b/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt
@@ -14,6 +14,9 @@ Release 2.0.4-beta - UNRELEASED
     HDFS-4304. Make FSEditLogOp.MAX_OP_SIZE configurable. (Colin Patrick
     McCabe via atm)
 
+    HDFS-4518. Finer grained metrics for HDFS capacity.
+    (Arpit Agarwal via suresh)
+
   OPTIMIZATIONS
 
   BUG FIXES
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/FSNamesystem.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/FSNamesystem.java
index b4e59f2fab4..af8a0dd5a74 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/FSNamesystem.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/FSNamesystem.java
@@ -3667,42 +3667,49 @@ public class FSNamesystem implements Namesystem, FSClusterStats,
     return stats;
   }
 
-  /**
-   * Total raw bytes including non-dfs used space.
-   */
   @Override // FSNamesystemMBean
+  @Metric({"CapacityTotal",
+      "Total raw capacity of data nodes in bytes"})
   public long getCapacityTotal() {
     return datanodeStatistics.getCapacityTotal();
   }
 
-  @Metric
+  @Metric({"CapacityTotalGB",
+      "Total raw capacity of data nodes in GB"})
   public float getCapacityTotalGB() {
     return DFSUtil.roundBytesToGB(getCapacityTotal());
   }
 
-  /**
-   * Total used space by data nodes
-   */
   @Override // FSNamesystemMBean
+  @Metric({"CapacityUsed",
+      "Total used capacity across all data nodes in bytes"})
   public long getCapacityUsed() {
     return datanodeStatistics.getCapacityUsed();
   }
 
-  @Metric
+  @Metric({"CapacityUsedGB",
+      "Total used capacity across all data nodes in GB"})
   public float getCapacityUsedGB() {
     return DFSUtil.roundBytesToGB(getCapacityUsed());
   }
 
-  @Override
+  @Override // FSNamesystemMBean
+  @Metric({"CapacityRemaining", "Remaining capacity in bytes"})
   public long getCapacityRemaining() {
     return datanodeStatistics.getCapacityRemaining();
   }
 
-  @Metric
+  @Metric({"CapacityRemainingGB", "Remaining capacity in GB"})
   public float getCapacityRemainingGB() {
     return DFSUtil.roundBytesToGB(getCapacityRemaining());
   }
 
+  @Metric({"CapacityUsedNonDFS",
+      "Total space used by data nodes for non DFS purposes in bytes"})
+  public long getCapacityUsedNonDFS() {
+    return datanodeStatistics.getCapacityUsedNonDFS();
+  }
+
   /**
    * Total number of connections.
    */
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/metrics/TestNameNodeMetrics.java b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/metrics/TestNameNodeMetrics.java
index 657db320100..e5616ae7ae1 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/metrics/TestNameNodeMetrics.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/metrics/TestNameNodeMetrics.java
@@ -129,7 +129,25 @@ public class TestNameNodeMetrics {
     stm.read(buffer,0,4);
     stm.close();
   }
-  
+
+  /**
+   * Test that capacity metrics are exported and pass
+   * basic sanity tests.
+   */
+  @Test (timeout = 1800)
+  public void testCapacityMetrics() throws Exception {
+    MetricsRecordBuilder rb = getMetrics(NS_METRICS);
+    long capacityTotal = MetricsAsserts.getLongGauge("CapacityTotal", rb);
+    assert(capacityTotal != 0);
+    long capacityUsed = MetricsAsserts.getLongGauge("CapacityUsed", rb);
+    long capacityRemaining =
+        MetricsAsserts.getLongGauge("CapacityRemaining", rb);
+    long capacityUsedNonDFS =
+        MetricsAsserts.getLongGauge("CapacityUsedNonDFS", rb);
+    assert(capacityUsed + capacityRemaining + capacityUsedNonDFS ==
+        capacityTotal);
+  }
+
   /** Test metrics indicating the number of stale DataNodes */
   @Test
   public void testStaleNodes() throws Exception {