HDFS-10984. Expose nntop output as metrics. Contributed by Siddharth Wagle.

(cherry picked from commit 61f0490a73)

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/FSNamesystem.java

@@ -98,6 +98,7 @@
 import static org.apache.hadoop.hdfs.server.namenode.FSDirStatAndListingOp.*;
 import static org.apache.hadoop.util.Time.now;
 import static org.apache.hadoop.util.Time.monotonicNow;
+import static org.apache.hadoop.hdfs.server.namenode.top.metrics.TopMetrics.TOPMETRICS_METRICS_SOURCE_NAME;
 
 import java.io.BufferedWriter;
 import java.io.ByteArrayInputStream;
@@ -976,6 +977,11 @@ private List<AuditLogger> initAuditLoggers(Configuration conf) {
     // Add audit logger to calculate top users
     if (topConf.isEnabled) {
       topMetrics = new TopMetrics(conf, topConf.nntopReportingPeriodsMs);
+      if (DefaultMetricsSystem.instance().getSource(
+          TOPMETRICS_METRICS_SOURCE_NAME) == null) {
+        DefaultMetricsSystem.instance().register(TOPMETRICS_METRICS_SOURCE_NAME,
+            "Top N operations by user", topMetrics);
+      }
       auditLoggers.add(new TopAuditLogger(topMetrics));
     }
 

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/top/metrics/TopMetrics.java

@@ -17,24 +17,32 @@
  */
 package org.apache.hadoop.hdfs.server.namenode.top.metrics;
 
-import java.net.InetAddress;
-import java.util.HashMap;
-import java.util.List;
-import java.util.Map;
-import java.util.Map.Entry;
-
 import com.google.common.collect.Lists;
+import org.apache.commons.lang.StringUtils;
 import org.apache.hadoop.classification.InterfaceAudience;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.fs.FileStatus;
 import org.apache.hadoop.hdfs.DFSConfigKeys;
 import org.apache.hadoop.hdfs.server.namenode.top.TopConf;
 import org.apache.hadoop.hdfs.server.namenode.top.window.RollingWindowManager;
+import org.apache.hadoop.hdfs.server.namenode.top.window.RollingWindowManager.Op;
+import org.apache.hadoop.hdfs.server.namenode.top.window.RollingWindowManager.User;
+import org.apache.hadoop.metrics2.MetricsCollector;
+import org.apache.hadoop.metrics2.MetricsInfo;
+import org.apache.hadoop.metrics2.MetricsRecordBuilder;
+import org.apache.hadoop.metrics2.MetricsSource;
+import org.apache.hadoop.metrics2.lib.Interns;
 import org.apache.hadoop.security.UserGroupInformation;
 import org.apache.hadoop.util.Time;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
+import java.net.InetAddress;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.Map.Entry;
+
 import static org.apache.hadoop.hdfs.server.namenode.top.window.RollingWindowManager.TopWindow;
 
 /**
@@ -58,8 +66,11 @@
  * Thread-safe: relies on thread-safety of RollingWindowManager
  */
 @InterfaceAudience.Private
-public class TopMetrics {
+public class TopMetrics implements MetricsSource {
   public static final Logger LOG = LoggerFactory.getLogger(TopMetrics.class);
+  public static final String TOPMETRICS_METRICS_SOURCE_NAME =
+      "NNTopUserOpCounts";
+  private final boolean isMetricsSourceEnabled;
 
   private static void logConf(Configuration conf) {
     LOG.info("NNTop conf: " + DFSConfigKeys.NNTOP_BUCKETS_PER_WINDOW_KEY +
@@ -83,6 +94,8 @@ public TopMetrics(Configuration conf, int[] reportingPeriods) {
       rollingWindowManagers.put(reportingPeriods[i], new RollingWindowManager(
           conf, reportingPeriods[i]));
     }
+    isMetricsSourceEnabled = conf.getBoolean(DFSConfigKeys.NNTOP_ENABLED_KEY,
+        DFSConfigKeys.NNTOP_ENABLED_DEFAULT);
   }
 
   /**
@@ -128,4 +141,44 @@ public void report(long currTime, String userName, String cmd) {
           TopConf.ALL_CMDS, userName, 1);
     }
   }
+
+  /**
+   * Flatten out the top window metrics into
+   * {@link org.apache.hadoop.metrics2.MetricsRecord}s for consumption by
+   * external metrics systems. Each metrics record added corresponds to the
+   * reporting period a.k.a window length of the configured rolling windows.
+   */
+  @Override
+  public void getMetrics(MetricsCollector collector, boolean all) {
+    if (!isMetricsSourceEnabled) {
+      return;
+    }
+
+    for (final TopWindow window : getTopWindows()) {
+      MetricsRecordBuilder rb = collector.addRecord(buildOpRecordName(window))
+          .setContext("dfs");
+      for (final Op op: window.getOps()) {
+        rb.addCounter(buildOpTotalCountMetricsInfo(op), op.getTotalCount());
+        for (User user : op.getTopUsers()) {
+          rb.addCounter(buildOpRecordMetricsInfo(op, user), user.getCount());
+        }
+      }
+    }
+  }
+
+  private String buildOpRecordName(TopWindow window) {
+    return TOPMETRICS_METRICS_SOURCE_NAME + ".windowMs="
+      + window.getWindowLenMs();
+  }
+
+  private MetricsInfo buildOpTotalCountMetricsInfo(Op op) {
+    return Interns.info("op=" + StringUtils.deleteWhitespace(op.getOpType())
+      + ".TotalCount", "Total operation count");
+  }
+
+  private MetricsInfo buildOpRecordMetricsInfo(Op op, User user) {
+    return Interns.info("op=" + StringUtils.deleteWhitespace(op.getOpType())
+      + ".user=" + user.getUser()
+      + ".count", "Total operations performed by user");
+  }
 }

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/metrics/TestTopMetrics.java

@@ -0,0 +1,63 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * <p>
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * <p>
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.hadoop.hdfs.server.namenode.metrics;
+
+import org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.hdfs.server.namenode.top.TopConf;
+import org.apache.hadoop.hdfs.server.namenode.top.metrics.TopMetrics;
+import org.apache.hadoop.metrics2.MetricsCollector;
+import org.apache.hadoop.metrics2.MetricsRecordBuilder;
+import org.apache.hadoop.metrics2.lib.Interns;
+import org.junit.Test;
+
+import static org.apache.hadoop.hdfs.server.namenode.top.metrics.TopMetrics.TOPMETRICS_METRICS_SOURCE_NAME;
+import static org.apache.hadoop.test.MetricsAsserts.getMetrics;
+import static org.mockito.Mockito.times;
+import static org.mockito.Mockito.verify;
+
+/**
+ * Test for MetricsSource part of the {@link TopMetrics} impl.
+ */
+public class TestTopMetrics {
+  @Test
+  public void testPresence() {
+    Configuration conf = new Configuration();
+    TopConf topConf = new TopConf(conf);
+    TopMetrics topMetrics = new TopMetrics(conf,
+        topConf.nntopReportingPeriodsMs);
+    // Dummy command
+    topMetrics.report("test", "listStatus");
+    topMetrics.report("test", "listStatus");
+    topMetrics.report("test", "listStatus");
+
+    MetricsRecordBuilder rb = getMetrics(topMetrics);
+    MetricsCollector mc = rb.parent();
+
+    verify(mc).addRecord(TOPMETRICS_METRICS_SOURCE_NAME + ".windowMs=60000");
+    verify(mc).addRecord(TOPMETRICS_METRICS_SOURCE_NAME + ".windowMs=300000");
+    verify(mc).addRecord(TOPMETRICS_METRICS_SOURCE_NAME + ".windowMs=1500000");
+
+    verify(rb, times(3)).addCounter(Interns.info("op=listStatus.TotalCount",
+        "Total operation count"), 3L);
+    verify(rb, times(3)).addCounter(Interns.info("op=*.TotalCount",
+        "Total operation count"), 3L);
+
+    verify(rb, times(3)).addCounter(Interns.info("op=listStatus." +
+        "user=test.count", "Total operations performed by user"), 3L);
+  }
+}