DRILL-4654: Add new metrics to the MetricRegistry

+ New metrics:
  - drill.queries.enqueued
    number of queries that have been submitted to the drillbit but have
    not started
  - drill.queries.running
    number of running queries for which this drillbit is the foreman
  - drill.queries.completed
    number of completed queries (or cancelled or failed) for which this
    drillbit was the foreman
  - drill.fragments.running
    number of query fragments that are running in the drillbit
  - drill.allocator.root.used
    amount of memory used in bytes by the internal memory allocator
  - drill.allocator.root.peak
    peak amount of memory used in bytes by the internal memory allocator
  - fd.usage
    ratio of used to total file descriptors (on *nix systems)
+ Rename "current" to "used" for RPC allocator current memory usage to
  follow convention
+ Borrow SystemPropertyUtil class from Netty
+ Configure DrillMetrics through system properties
+ Remove unused methods and imports

closes #495

1 files changed, 4 insertions, 5 deletions

diff --git a/exec/java-exec/src/main/java/org/apache/drill/exec/service/ServiceEngine.java b/exec/java-exec/src/main/java/org/apache/drill/exec/service/ServiceEngine.java
index 17edbc26e..d5055461c 100644
--- a/exec/java-exec/src/main/java/org/apache/drill/exec/service/ServiceEngine.java
+++ b/exec/java-exec/src/main/java/org/apache/drill/exec/service/ServiceEngine.java
@@ -28,7 +28,6 @@ import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Executors;
 import java.util.concurrent.TimeUnit;
 
-import org.apache.commons.lang3.StringUtils;
 import org.apache.drill.common.AutoCloseables;
 import org.apache.drill.common.config.DrillConfig;
 import org.apache.drill.exec.ExecConstants;
@@ -92,9 +91,9 @@ public class ServiceEngine implements AutoCloseable {
 
   }
 
-  private final void registerMetrics(final MetricRegistry registry) {
+  private void registerMetrics(final MetricRegistry registry) {
     final String prefix = PooledByteBufAllocatorL.METRIC_PREFIX + "rpc.";
-    DrillMetrics.register(prefix + "user.current", new Gauge<Long>() {
+    DrillMetrics.register(prefix + "user.used", new Gauge<Long>() {
       @Override
       public Long getValue() {
         return userAllocator.getAllocatedMemory();
@@ -106,7 +105,7 @@ public class ServiceEngine implements AutoCloseable {
         return userAllocator.getPeakMemoryAllocation();
       }
     });
-    DrillMetrics.register(prefix + "bit.control.current", new Gauge<Long>() {
+    DrillMetrics.register(prefix + "bit.control.used", new Gauge<Long>() {
       @Override
       public Long getValue() {
         return controlAllocator.getAllocatedMemory();
@@ -119,7 +118,7 @@ public class ServiceEngine implements AutoCloseable {
       }
     });
 
-    DrillMetrics.register(prefix + "bit.data.current", new Gauge<Long>() {
+    DrillMetrics.register(prefix + "bit.data.used", new Gauge<Long>() {
       @Override
       public Long getValue() {
         return dataAllocator.getAllocatedMemory();