adding performance counters

git-svn-id: https://hudson.dev.java.net/svn/hudson/trunk/hudson/main@6613 71c3de6d-444a-0410-be80-ed276b4c234a

remoting/src/main/java/hudson/remoting/Channel.java

@@ -18,6 +18,8 @@ import java.util.Vector;
 import java.util.concurrent.ExecutionException;
 import java.util.concurrent.Executor;
 import java.util.concurrent.ExecutorService;
+import java.util.concurrent.atomic.AtomicLong;
+import java.util.concurrent.atomic.AtomicInteger;
 import java.util.logging.Level;
 import java.util.logging.Logger;
 
@@ -113,6 +115,40 @@ public class Channel implements VirtualChannel {
     private final Vector<Listener> listeners = new Vector<Listener>();
     private int gcCounter;
 
+    /**
+     * Total number of nanoseconds spent for remote class loading.
+     * <p>
+     * Remote code execution often results in classloading activity
+     * (more precisely, when the remote peer requests some computation
+     * on this channel, this channel often has to load necessary
+     * classes from the remote peer.)
+     * <p>
+     * This counter represents the total amount of time this channel
+     * had to spend loading classes from the remote peer. The time
+     * measurement doesn't include the time locally spent to actually
+     * define the class (as the local classloading would have incurred
+     * the same cost.)
+     */
+    public final AtomicLong classLoadingTime = new AtomicLong();
+
+    /**
+     * Total counts of remote classloading activities. Used in a pair
+     * with {@link #classLoadingTime}.
+     */
+    public final AtomicInteger classLoadingCount = new AtomicInteger();
+
+    /**
+     * Total number of nanoseconds spent for remote resource loading.
+     * @see #classLoadingTime
+     */
+    public final AtomicLong resourceLoadingTime = new AtomicLong();
+
+    /**
+     * Total count of remote resource loading.
+     * @see #classLoadingCount
+     */
+    public final AtomicInteger resourceLoadingCount = new AtomicInteger();
+
     /**
      * Communication mode.
      * @since 1.161
@@ -478,6 +514,16 @@ public class Channel implements VirtualChannel {
         private static final long serialVersionUID = 1L;
     }
 
+    /**
+     * Resets all the performance counters.
+     */
+    public void resetPerformanceCounters() {
+        classLoadingCount.set(0);
+        classLoadingTime.set(0);
+        resourceLoadingCount.set(0);
+        resourceLoadingTime.set(0);
+    }
+
     /**
      * {@inheritDoc}
      */

remoting/src/main/java/hudson/remoting/RemoteClassLoader.java

@@ -21,6 +21,10 @@ import java.util.ArrayList;
  */
 final class RemoteClassLoader extends ClassLoader {
     private final IClassLoader proxy;
+    /**
+     * Remote peer that the {@link #proxy} is connected to.
+     */
+    private final Channel channel;
 
     private final Map<String,URL> resourceMap = new HashMap<String,URL>();
     private final Map<String,Vector<URL>> resourcesMap = new HashMap<String,Vector<URL>>();
@@ -38,10 +42,14 @@ final class RemoteClassLoader extends ClassLoader {
     private RemoteClassLoader(ClassLoader parent, IClassLoader proxy) {
         super(parent);
         this.proxy = proxy;
+        this.channel = RemoteInvocationHandler.unwrap(proxy);
     }
 
     protected Class<?> findClass(String name) throws ClassNotFoundException {
+        long startTime = System.nanoTime();
         byte[] bytes = proxy.fetch(name);
+        channel.classLoadingTime.addAndGet(System.nanoTime()-startTime);
+        channel.classLoadingCount.incrementAndGet();
         return defineClass(name, bytes, 0, bytes.length);
     }
 
@@ -50,7 +58,10 @@ final class RemoteClassLoader extends ClassLoader {
             return resourceMap.get(name);
 
         try {
+            long startTime = System.nanoTime();
             byte[] image = proxy.getResource(name);
+            channel.resourceLoadingTime.addAndGet(System.nanoTime()-startTime);
+            channel.resourceLoadingCount.incrementAndGet();
             if(image==null) {
                 resourceMap.put(name,null);
                 return null;
@@ -69,7 +80,10 @@ final class RemoteClassLoader extends ClassLoader {
         if(urls!=null)
             return urls.elements();
 
+        long startTime = System.nanoTime();
         byte[][] images = proxy.getResources(name);
+        channel.resourceLoadingTime.addAndGet(System.nanoTime()-startTime);
+        channel.resourceLoadingCount.incrementAndGet();
 
         urls = new Vector<URL>();
         for( byte[] image: images )