svn commit: r1464713 - /aries/trunk/subsystem/subsystem-core/src/main/java/org/apache/aries/subsystem/core/internal/BasicSubsystem.java

[jw...@apache.org]

Author: jwross
Date: Thu Apr  4 19:55:54 2013
New Revision: 1464713

URL: http://svn.apache.org/r1464713
Log:
[ARIES-1034] Excessive IO when install subsystems and when initializing the root subsystem

Minimize IO time caused by writing to the deployment manifest by participating in the current thread coordination and
writing once when the coordination ends. If there is no coordination in progress, write immediately as before.

Modified:
    aries/trunk/subsystem/subsystem-core/src/main/java/org/apache/aries/subsystem/core/internal/BasicSubsystem.java

Modified: aries/trunk/subsystem/subsystem-core/src/main/java/org/apache/aries/subsystem/core/internal/BasicSubsystem.java
URL: http://svn.apache.org/viewvc/aries/trunk/subsystem/subsystem-core/src/main/java/org/apache/aries/subsystem/core/internal/BasicSubsystem.java?rev=1464713&r1=1464712&r2=1464713&view=diff
==============================================================================
--- aries/trunk/subsystem/subsystem-core/src/main/java/org/apache/aries/subsystem/core/internal/BasicSubsystem.java (original)
+++ aries/trunk/subsystem/subsystem-core/src/main/java/org/apache/aries/subsystem/core/internal/BasicSubsystem.java Thu Apr  4 19:55:54 2013
@@ -13,6 +13,7 @@
  */
 package org.apache.aries.subsystem.core.internal;
 
+import java.io.BufferedOutputStream;
 import java.io.File;
 import java.io.FileOutputStream;
 import java.io.IOException;
@@ -24,11 +25,13 @@ import java.util.ArrayList;
 import java.util.Collection;
 import java.util.Collections;
 import java.util.EnumSet;
+import java.util.HashSet;
 import java.util.Iterator;
 import java.util.List;
 import java.util.Locale;
 import java.util.Map;
 import java.util.Map.Entry;
+import java.util.Set;
 
 import org.apache.aries.subsystem.AriesSubsystem;
 import org.apache.aries.subsystem.core.archive.AriesSubsystemParentsHeader;
@@ -485,17 +488,39 @@ public class BasicSubsystem implements R
 		}
 	}
 	
-	synchronized void setDeploymentManifest(DeploymentManifest value) throws IOException, URISyntaxException {
+	synchronized void setDeploymentManifest(DeploymentManifest value) throws IOException {
+		deploymentManifest = value;
+		Coordination coordination = Activator.getInstance().getCoordinator().peek();
+		if (coordination == null) {
+			saveDeploymentManifest();
+		} else {
+			Map<Class<?>, Object> variables = coordination.getVariables();
+			synchronized (variables) {
+				@SuppressWarnings("unchecked")
+				Set<BasicSubsystem> dirtySubsystems = (Set<BasicSubsystem>) variables.get(SaveManifestParticipant.class);
+				if (dirtySubsystems == null) {
+					// currently no dirty subsystems found;
+					// create a list to hold them and store it as a variable
+					dirtySubsystems = new HashSet<BasicSubsystem>();
+					variables.put(SaveManifestParticipant.class, dirtySubsystems);
+					// add the save manifest participant
+					coordination.addParticipant(new SaveManifestParticipant());
+				}
+				dirtySubsystems.add(this);
+			}
+		}
+	}
+
+	synchronized void saveDeploymentManifest() throws IOException {
 		File file = new File(getDirectory(), "OSGI-INF");
 		if (!file.exists())
 			file.mkdirs();
-		FileOutputStream fos = new FileOutputStream(new File(file, "DEPLOYMENT.MF"));
+		BufferedOutputStream out = new BufferedOutputStream(new FileOutputStream(new File(file, "DEPLOYMENT.MF")));
 		try {
-			value.write(fos);
-			deploymentManifest = value;
+			deploymentManifest.write(out);
 		}
 		finally {
-			IOUtils.close(fos);
+			IOUtils.close(out);
 		}
 	}
 	
@@ -559,4 +584,28 @@ public class BasicSubsystem implements R
 	public AriesSubsystem install(String location, IDirectory content) {
 		return AccessController.doPrivileged(new InstallAction(location, content, this, AccessController.getContext()));
 	}
+
+	private static class SaveManifestParticipant implements Participant {
+		protected SaveManifestParticipant() {}
+
+		@Override
+		public void ended(Coordination coordination) throws Exception {
+			Map<Class<?>, Object> variables = coordination.getVariables();
+			Set<BasicSubsystem> dirtySubsystems;
+			synchronized (variables) {
+				@SuppressWarnings("unchecked")
+				Set<BasicSubsystem> temp = (Set<BasicSubsystem>) variables.remove(SaveManifestParticipant.class);
+				dirtySubsystems = temp == null ? Collections. <BasicSubsystem>emptySet() : temp;
+			}
+			for (BasicSubsystem dirtySubsystem : dirtySubsystems) {
+				dirtySubsystem.saveDeploymentManifest();
+			}
+		}
+
+		@Override
+		public void failed(Coordination coordination) throws Exception {
+			// Do no saving
+		}
+		
+	}
 }