diff --git a/source/de/anomic/http/server/HTTPDFileHandler.java b/source/de/anomic/http/server/HTTPDFileHandler.java
index 9ec7f6bfa..cbdbd17b4 100644
--- a/source/de/anomic/http/server/HTTPDFileHandler.java
+++ b/source/de/anomic/http/server/HTTPDFileHandler.java
@@ -1192,26 +1192,6 @@ public final class HTTPDFileHandler {
     
     public static final Object invokeServlet(final File targetClass, final RequestHeader request, final serverObjects args) throws IllegalArgumentException, IllegalAccessException, InvocationTargetException {
         // debug functions: for special servlets call them without reflection to get better stack trace results
-        /*
-        if (targetClass.getName().equals("transferURL.class")) {
-            try {
-                return transferURL.respond(request, args, switchboard);
-            } catch (Exception e) {
-                Log.logException(e);
-                Log.logSevere("HTTPFileHandler", "fail of transferURL", e);
-                throw new InvocationTargetException(e);
-            }
-        }
-        if (targetClass.getName().equals("crawlReceipt.class")) {
-            try {
-                return crawlReceipt.respond(request, args, switchboard);
-            } catch (Exception e) {
-                Log.logException(e);
-                Log.logSevere("HTTPFileHandler", "fail of crawlReceipt", e);
-                throw new InvocationTargetException(e);
-            }
-        }
-        */
         Object result;
         if (safeServletsMode) synchronized (switchboard) {
             result = rewriteMethod(targetClass).invoke(null, new Object[] {request, args, switchboard});
diff --git a/source/de/anomic/server/serverCore.java b/source/de/anomic/server/serverCore.java
index 86d6f900a..27a677c86 100644
--- a/source/de/anomic/server/serverCore.java
+++ b/source/de/anomic/server/serverCore.java
@@ -94,7 +94,7 @@ public final class serverCore extends AbstractBusyThread implements BusyThread {
     public  static final Class<?>[] sessionCallType = {String.class, Session.class}; //  set up some reflection
     public  static final long startupTime = System.currentTimeMillis();
     private static final ThreadGroup sessionThreadGroup = new ThreadGroup("sessionThreadGroup");
-    private static final Map<String, Object> commandObjMethodCache = new ConcurrentHashMap<String, Object>(5);
+    private static final Map<String, Method> commandObjMethodCache = new ConcurrentHashMap<String, Method>(5);
     
     /**
      * will be increased with each session and is used to return a hash code
@@ -713,7 +713,7 @@ public final class serverCore extends AbstractBusyThread implements BusyThread {
                         this.controlSocket.setSoTimeout(this.socketTimeout);
                         
                         // exec command and return value
-                        Object commandMethod = commandObjMethodCache.get(reqProtocol + "_" + reqCmd);
+                        Method commandMethod = commandObjMethodCache.get(reqProtocol + "_" + reqCmd);
                         if (commandMethod == null) {
                             try {
                                 commandMethod = this.commandObj.getClass().getMethod(reqCmd, sessionCallType);
@@ -724,7 +724,7 @@ public final class serverCore extends AbstractBusyThread implements BusyThread {
                             }
                         }
                         //long commandStart = System.currentTimeMillis();
-                        Object result = ((Method)commandMethod).invoke(this.commandObj, parameter);
+                        Object result = commandMethod.invoke(this.commandObj, parameter);
                         //announceMoreExecTime(commandStart - System.currentTimeMillis()); // shall be negative!
                         //this.log.logDebug("* session " + handle + " completed command '" + request + "'. time = " + (System.currentTimeMillis() - handle));
                         this.out.flush();
diff --git a/source/net/yacy/dbtest.java b/source/net/yacy/dbtest.java
index 3c6773d1b..d4a4c66ce 100644
--- a/source/net/yacy/dbtest.java
+++ b/source/net/yacy/dbtest.java
@@ -463,6 +463,7 @@ final class memprofiler extends Thread {
         } catch (final Exception e) {
             Log.logException(e);
         }
+        ImageIO.setUseCache(false);
         try {
             ImageIO.write(memChart.getImage(), "png", outputFile);
         } catch (final IOException e) {
diff --git a/source/net/yacy/gui/YaCyApp.java b/source/net/yacy/gui/YaCyApp.java
index 0f0e23e05..554e0358e 100644
--- a/source/net/yacy/gui/YaCyApp.java
+++ b/source/net/yacy/gui/YaCyApp.java
@@ -57,6 +57,7 @@ public class YaCyApp {
     static {
         try {
             javax.swing.UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
+            ImageIO.setUseCache(false); // do not write a cache to disc; keep in RAM
             if (splashFile != null) splashImg = ImageIO.read(splashFile);
         } catch(Exception e) {
             e.printStackTrace();