Adding new listener to defragement heap at startup.

webapp/src/edu/cornell/mannlib/vitro/webapp/servlet/setup/HeapDefragement.java

@@ -0,0 +1,40 @@
+package edu.cornell.mannlib.vitro.webapp.servlet.setup;
+
+import javax.servlet.ServletContextEvent;
+import javax.servlet.ServletContextListener;
+
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
+
+/**
+ * This class will request a full garbage collection when 
+ * contextInitialized() is called.  The goal is to eliminate fragmentation
+ * in the tenured generation and avoid problems with the 'young generation guarantee.'
+ * 
+ * This should be the last listener before the context starts.
+ * 
+ * See http://blogs.sun.com/jonthecollector/entry/when_the_sum_of_the (retrieved 2010-10-18)
+ * 
+ * @author bdc34
+ *
+ */
+public class HeapDefragement implements ServletContextListener {
+    private static final Log log = LogFactory.getLog(HeapDefragement.class);
+    
+    @Override
+    public void contextInitialized(ServletContextEvent arg0) {
+        try{
+            log.info("Calling System.gc() to defragement the heap.");
+            long start = System.currentTimeMillis();
+            System.gc();           
+            log.info("GC took " + (System.currentTimeMillis() - start) + " msec");
+        }catch(Exception ex){
+            log.error(ex,ex);            
+        }                
+    }
+    
+    @Override
+    public void contextDestroyed(ServletContextEvent arg0) {
+        //do nothing        
+    }
+}