diff --git a/x0vncserver/PollingManager.cxx b/x0vncserver/PollingManager.cxx
index 0c972dd..f131e7e 100644
--- a/x0vncserver/PollingManager.cxx
+++ b/x0vncserver/PollingManager.cxx
@@ -26,7 +26,6 @@
 #include <stdio.h>
 #include <string.h>
 #include <time.h>
-#include <sys/time.h>
 #include <X11/Xlib.h>
 #include <rfb/VNCServer.h>
 #include <rfb/Configuration.h>
@@ -96,6 +95,10 @@
   memset(m_rateMatrix, 0, numTiles);
   memset(m_videoFlags, 0, numTiles);
   memset(m_changedFlags, 0, numTiles);
+
+#ifdef DEBUG
+  memset(&m_timeSaved, 0, sizeof(m_timeSaved));
+#endif
 }
 
 PollingManager::~PollingManager()
@@ -142,33 +145,45 @@
 }
 
 //
-// DEBUG: a version of poll() measuring time spent in the function.
+// DEBUG: Measuring time spent in the poll() function,
+//        as well as time intervals between poll() calls.
 //
 
-void PollingManager::pollDebug()
+#ifdef DEBUG
+void PollingManager::debugBeforePoll()
 {
-  struct timeval timeSaved, timeNow;
+  struct timeval timeNow;
   struct timezone tz;
-  timeSaved.tv_sec = 0;
-  timeSaved.tv_usec = 0;
-  gettimeofday(&timeSaved, &tz);
-  int step = m_pollingStep;
-
-  poll();
-
   gettimeofday(&timeNow, &tz);
-  int diff = (int)((timeNow.tv_usec - timeSaved.tv_usec + 500) / 1000 +
-                   (timeNow.tv_sec - timeSaved.tv_sec) * 1000);
-  if (diff != 0)
-    fprintf(stderr, "DEBUG: poll(): %4d ms [step %2d]\n", diff, step % 32);
+  int diff = (int)((timeNow.tv_usec - m_timeSaved.tv_usec + 500) / 1000 +
+                   (timeNow.tv_sec - m_timeSaved.tv_sec) * 1000);
+  fprintf(stderr, "[wait%4dms]\t[step %2d]\t", diff, m_pollingStep % 32);
+  m_timeSaved = timeNow;
 }
 
+void PollingManager::debugAfterPoll()
+{
+  struct timeval timeNow;
+  struct timezone tz;
+  gettimeofday(&timeNow, &tz);
+  int diff = (int)((timeNow.tv_usec - m_timeSaved.tv_usec + 500) / 1000 +
+                   (timeNow.tv_sec - m_timeSaved.tv_sec) * 1000);
+  fprintf(stderr, "[poll%4dms]\n", diff);
+  m_timeSaved = timeNow;
+}
+
+#endif
+
 //
 // Search for changed rectangles on the screen.
 //
 
 void PollingManager::poll()
 {
+#ifdef DEBUG
+  debugBeforePoll();
+#endif
+
   // First step: full-screen polling.
 
   bool changes1 = false;
@@ -206,6 +221,10 @@
 
   if (changes1 || changes2)
     m_server->tryUpdate();
+
+#ifdef DEBUG
+  debugAfterPoll();
+#endif
 }
 
 bool PollingManager::poll_DetectVideo()
diff --git a/x0vncserver/PollingManager.h b/x0vncserver/PollingManager.h
index 04cc767..a56d2e4 100644
--- a/x0vncserver/PollingManager.h
+++ b/x0vncserver/PollingManager.h
@@ -23,6 +23,8 @@
 #ifndef __POLLINGMANAGER_H__
 #define __POLLINGMANAGER_H__
 
+#include <sys/time.h>
+
 #include <X11/Xlib.h>
 #include <rfb/VNCServer.h>
 
@@ -42,7 +44,6 @@
   void setPointerPos(const Point &pos);
   void unsetPointerPos();
 
-  void pollDebug();
   void poll();
 
   // Configurable parameters.
@@ -96,6 +97,15 @@
   unsigned int m_pollingStep;
   static const int m_pollingOrder[];
 
+#ifdef DEBUG
+private:
+
+  void debugBeforePoll();
+  void debugAfterPoll();
+
+  struct timeval m_timeSaved;
+#endif
+
 };
 
 #endif // __POLLINGMANAGER_H__
diff --git a/x0vncserver/x0vncserver.cxx b/x0vncserver/x0vncserver.cxx
index 1ea2e81..e69fa93 100644
--- a/x0vncserver/x0vncserver.cxx
+++ b/x0vncserver/x0vncserver.cxx
@@ -443,16 +443,19 @@
           int coeff = cpumon.check();
           if (coeff < 90 || coeff > 110) {
             // Adjust polling cycle to satisfy MaxProcessorUsage setting
+#ifdef DEBUG
+            int oldPollingCycle = dynPollingCycle;
+#endif
             dynPollingCycle = (dynPollingCycle * 100 + coeff/2) / coeff;
             if (dynPollingCycle < (int)pollingCycle) {
               dynPollingCycle = (int)pollingCycle;
             } else if (dynPollingCycle > (int)pollingCycle * 32) {
               dynPollingCycle = (int)pollingCycle * 32;
             }
-            // DEBUG:
-            // if (dynPollingCycle != old) {
-            //   fprintf(stderr, "[%dms]\t", dynPollingCycle);
-            // }
+#ifdef DEBUG
+            if (dynPollingCycle != oldPollingCycle)
+              fprintf(stderr, "\t[new cycle %dms]\n", dynPollingCycle);
+#endif
           }
           desktop.poll();
         }