diff --git a/composite.cpp b/composite.cpp
index e964950281..e8cdadd757 100644
--- a/composite.cpp
+++ b/composite.cpp
@@ -52,10 +52,14 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #include "scene_xrender.h"
 #include "scene_opengl.h"
 #include "compositingprefs.h"
+#include "notifications.h"
 
 #include <stdio.h>
 
 #include <QMenu>
+#include <kaction.h>
+#include <kactioncollection.h>
+#include <klocale.h>
 #include <kxerrorhandler.h>
 
 #include <X11/extensions/shape.h>
@@ -193,6 +197,7 @@ void Workspace::setupCompositing()
     nextPaintReference = QTime::currentTime().addMSecs( -compositeRate );
     compositeTimer.setSingleShot( true );
     checkCompositeTimer();
+    composite_paint_times.clear();
     XCompositeRedirectSubwindows( display(), rootWindow(), CompositeRedirectManual );
     new EffectsHandlerImpl( scene->compositingType() ); // sets also the 'effects' pointer
     addRepaintFull();
@@ -269,7 +274,17 @@ void Workspace::lostCMSelection()
 // for the shortcut
 void Workspace::slotToggleCompositing()
     {
-    compositingSuspended = !compositingSuspended;
+    suspendCompositing( !compositingSuspended );
+    }
+    
+void Workspace::suspendCompositing()
+    {
+    suspendCompositing( true );
+    }
+
+void Workspace::suspendCompositing( bool suspend )
+    {
+    compositingSuspended = suspend;
     finishCompositing();
     setupCompositing(); // will do nothing if suspended
     }
@@ -365,6 +380,7 @@ void Workspace::performCompositing()
     QRegion repaints = repaints_region;
     // clear all repaints, so that post-pass can add repaints for the next repaint
     repaints_region = QRegion();
+    QTime t = QTime::currentTime();
     scene->paint( repaints, windows );
     if( scene->waitSyncAvailable())
         {
@@ -381,6 +397,7 @@ void Workspace::performCompositing()
     // checkCompositeTime() would restart it again somewhen later, called from functions that
     // would again add something pending.
     checkCompositeTimer();
+    checkCompositePaintTime( t.elapsed());
     lastCompositePaint.start();
 #endif
     }
@@ -428,6 +445,35 @@ bool Workspace::createOverlay()
 #endif
     }
 
+void Workspace::checkCompositePaintTime( int msec )
+    {
+    if( options->disableCompositingChecks )
+        return;
+    composite_paint_times.enqueue( msec );
+    if( composite_paint_times.count() > 3 )
+        composite_paint_times.dequeue();
+    if( composite_paint_times.count() < 3 )
+        return;
+    // If last 3 paints were way too slow, disable and warn.
+    // 1 second seems reasonable, it's not that difficult to get relatively high times
+    // with high system load.
+    const int MAX_TIME = 1000;
+    if( composite_paint_times[ 0 ] > MAX_TIME && composite_paint_times[ 1 ] > MAX_TIME
+        && composite_paint_times[ 2 ] > MAX_TIME )
+        {
+        kDebug( 1212 ) << "Too long paint times, suspending";
+        QTimer::singleShot( 0, this, SLOT( suspendCompositing()));
+        QString shortcut = i18n( "Empty" );
+        if( KAction* action = qobject_cast<KAction*>( keys->action("Suspend Compositing")))
+            shortcut = action->globalShortcut().primary().toString();
+        QString message = i18n( "Compositing was too slow and has been suspended.\n"
+            "If this was only a temporary problem, you can resume using the '%1' shortcut.\n"
+            "You can also disable functionality checks in advanced compositing settings.", shortcut );
+        Notify::raise( Notify::CompositingSlow, message );
+        compositeTimer.start( 1000 ); // so that it doesn't trigger sooner than suspendCompositing()
+        }
+    }
+
 void Workspace::setupOverlay( Window w )
     {
     assert( overlay != None );
diff --git a/kwin.notifyrc b/kwin.notifyrc
index c77ee8e5a3..b763aa374c 100644
--- a/kwin.notifyrc
+++ b/kwin.notifyrc
@@ -5485,3 +5485,7 @@ Comment[x-test]=xxA window on an inactive virtual desktop demands attentionxx
 Comment[zh_CN]=未激活的虚拟桌面上的窗口请求注意
 Comment[zh_TW]=在其他虛擬桌面上的視窗要求注意
 
+[Event/compositingslow]
+Name=Compositing Performance Is Slow
+Comment=The compositing performance was too slow and compositing has been suspended
+Action=Popup
diff --git a/notifications.cpp b/notifications.cpp
index 149df1880c..a45e85d9c7 100644
--- a/notifications.cpp
+++ b/notifications.cpp
@@ -27,9 +27,16 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 namespace KWin
 {
 
-QString Notify::eventToName( Event e )
+static bool forgetIt = false;
+QList< Notify::EventData > Notify::pending_events;
+
+bool Notify::raise( Event e, const QString& message, Client* c )
     {
+    if ( forgetIt )
+        return false; // no connection was possible, don't try each time
+
     QString event;
+    KNotification::NotificationFlags flags = KNotification::CloseOnTimeout;
     switch ( e ) 
         {
         case Activate:
@@ -92,6 +99,10 @@ QString Notify::eventToName( Event e )
         case DemandAttentionOther:
             event = "demandsattentionother";
             break;
+        case CompositingSlow:
+            event = "compositingslow";
+            flags = KNotification::Persistent;
+            break;
         default:
             if ((e > DesktopChange) && (e <= DesktopChange+20))
             {
@@ -99,18 +110,6 @@ QString Notify::eventToName( Event e )
             }
         break;
         }
-    return event;
-    }
-
-static bool forgetIt = false;
-QList< Notify::EventData > Notify::pending_events;
-
-bool Notify::raise( Event e, const QString& message, Client* c )
-    {
-    if ( forgetIt )
-        return false; // no connection was possible, don't try each time
-
-    QString event = eventToName( e );
     if ( event.isNull() )
         return false;
 
@@ -124,12 +123,13 @@ bool Notify::raise( Event e, const QString& message, Client* c )
         data.event = event;
         data.message = message;
         data.window = c ? c->window() : 0;
+        data.flags = flags;
         pending_events.append( data );
         return true;
         }
 
     
-    return KNotification::event( event, message /*, QPixmap() , c ? c->window() : 0*/ ); //FIXME get the widget ?
+    return KNotification::event( event, message, QPixmap(), NULL /* TODO c ? c->window() : 0*/, flags );
     }
 
 void Notify::sendPendingEvents()
@@ -139,7 +139,7 @@ void Notify::sendPendingEvents()
         EventData data = pending_events.first();
         pending_events.pop_front();
         if( !forgetIt )
-            KNotification::event( data.event, data.message /*  , QPixmap() , data.window  */ );
+            KNotification::event( data.event, data.message, QPixmap(), NULL /* TODO data.window*/, data.flags );
         }
     }
 
diff --git a/notifications.h b/notifications.h
index 6fdf78cc0b..5d7c3b0c62 100644
--- a/notifications.h
+++ b/notifications.h
@@ -22,6 +22,7 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #ifndef KWIN_NOTIFICATIONS_H
 #define KWIN_NOTIFICATIONS_H
 
+#include <knotification.h>
 #include <stdlib.h>
 #include <QString>
 #include <QList>
@@ -57,18 +58,19 @@ class Notify
             ResizeEnd,
             DemandAttentionCurrent,
             DemandAttentionOther,
+            CompositingSlow,
             DesktopChange = 100
             };
 
         static bool raise( Event, const QString& message = QString(), Client* c = NULL );
         static void sendPendingEvents();
     private:
-        static QString eventToName( Event );
         struct EventData
             {
             QString event;
             QString message;
             long window;
+            KNotification::NotificationFlags flags;
             };
         static QList< EventData > pending_events;
     };
diff --git a/workspace.h b/workspace.h
index 9ee48985ea..906ad163c9 100644
--- a/workspace.h
+++ b/workspace.h
@@ -30,6 +30,7 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #include <kxmessages.h>
 #include <QDateTime>
 #include <kmanagerselection.h>
+#include <qqueue.h>
 
 #include "utils.h"
 #include "kdecoration.h"
@@ -472,6 +473,8 @@ class Workspace : public QObject, public KDecorationDefines
         void slotToggleCompositing();
 
         void updateClientArea();
+        void suspendCompositing();
+        void suspendCompositing( bool suspend );
 
     private slots:
         void desktopPopupAboutToShow();
@@ -577,6 +580,7 @@ class Workspace : public QObject, public KDecorationDefines
         void finishCompositing();
         bool windowRepaintsPending() const;
         void setCompositeTimer();
+        void checkCompositePaintTime( int msec );
 
         int current_desktop;
         int number_of_desktops;
@@ -749,6 +753,7 @@ class Workspace : public QObject, public KDecorationDefines
         QPushButton *transButton;
         QTimer unredirectTimer;
         bool forceUnredirectCheck;
+        QQueue< int > composite_paint_times;
 
     private:
         friend bool performTransiencyCheck();