Index: leahi_dialin/dd/modules/substitution_pump.py
===================================================================
diff -u -r3e2f7365bb1a643d2fc9bea2dc51f4b15f0ba9e2 -r820c94585ab5d85c40395e828c4dfe2da164c105
--- leahi_dialin/dd/modules/substitution_pump.py	(.../substitution_pump.py)	(revision 3e2f7365bb1a643d2fc9bea2dc51f4b15f0ba9e2)
+++ leahi_dialin/dd/modules/substitution_pump.py	(.../substitution_pump.py)	(revision 820c94585ab5d85c40395e828c4dfe2da164c105)
@@ -15,7 +15,7 @@
 ############################################################################
 
 # Module imports
-import struct
+import time
 from logging import Logger
 
 # Project imports
@@ -61,6 +61,7 @@
             }
         }
         self.dd_substitution_pump_timestamp = 0  #: The timestamp of the latest message
+        self.handler_execution_times = []
 
     @publish(["msg_id_dd_rinse_pump_data",
               "dd_substitution_pumps",
@@ -72,6 +73,7 @@
         @param message:  published substitution pump data message
         @return: None
         """
+        start = time.perf_counter()
         substitution_pump_list = []
         substitution_pump_list.append((dd_enum_repository.DDSubstitutionPumpNames.D92_PUMP.name, dd_enum_repository.DDSubstitutionPumpAttributes.TARGET_SPEED.name,   DataTypes.F32))
         substitution_pump_list.append((dd_enum_repository.DDSubstitutionPumpNames.D92_PUMP.name, dd_enum_repository.DDSubstitutionPumpAttributes.CURRENT_SPEED.name,  DataTypes.F32))
@@ -83,6 +85,7 @@
                                message = message)
 
         self.dd_substitution_pump_timestamp = timestamp
+        self.handler_execution_times.append(time.perf_counter() - start)
 
     def cmd_substitution_pump_data_publish_interval_override(self, ms: int, reset: int = NO_RESET) -> int:
         """