def test_event_chain(self):
"""
Test module EventChain. Add and remove SimEvents and check the correct order.
"""
# priorities: SC = 0, CA = 1, ST = 2
e = EventChain()
e.insert(CustomerArrival(None, 10))
e.insert(SimulationTermination(None, 10))
e.insert(ServiceCompletion(None, 10))
e.insert(CustomerArrival(None, 5))
e.insert(ServiceCompletion(None, 2))
results = [[2, 0], [5, 1], [10, 0], [10, 1], [10, 2]]
for r in results:
ev = e.remove_oldest_event()
self.assertEqual(
[ev.timestamp, ev.priority],
r,
msg=
"Error in EventChain or SimEvent. Events are sorted or returned in the wrong order."
)
self.assertEqual(
len(e.event_list),
0,
msg="Error in EventChain or SimEvent. EventChain should be empty.")
def test_service_completion(self):
"""
Test ServiceCompletion process function. Check, whether processing of service completion events works as
desired (making server idle again or triggering new service start).
"""
DESTest.sim.reset()
# initialize system
DESTest.sim.system_state.buffer_content = 1
DESTest.sim.system_state.server_busy = True
self.assertEqual([DESTest.sim.system_state.buffer_content, DESTest.sim.system_state.server_busy], [1, True],
msg="Error in ServiceCompletion test. Initialization failed.")
# first service completion should insert new service completion and take packet from queue
ServiceCompletion(DESTest.sim, 0).process()
self.assertEqual([DESTest.sim.system_state.buffer_content, DESTest.sim.system_state.server_busy], [0, True],
msg="Error in ServiceCompletion. Server should be busy and queue should be empty.")
self.assertEqual(len(DESTest.sim.event_chain.event_list), 1,
msg="Error in ServiceCompletion. Wrong number of new SimEvents created in process function.")
# second service completion should make server idle again
ServiceCompletion(DESTest.sim, 0).process()
self.assertEqual([DESTest.sim.system_state.buffer_content, DESTest.sim.system_state.server_busy], [0, False],
msg="Error in ServiceCompletion. Server should be idle and queue should be empty.")
self.assertEqual(len(DESTest.sim.event_chain.event_list), 1,
msg="Error in ServiceCompletion. Wrong number of new SimEvents created in process function.")
def pause_service(self):
"""
If the buffer is not empty, take the next packet from there and serve it.
:return: True if buffer is not empty and a stored packet is being served.
"""
#self.counter_collection.count_throughput(self.served_packet.get_throughput()) # firstly throughput is calculated
#self.event_chain.event_list.remove(ServiceCompletion(self, self.served_packet.t_finish))
self.event_chain.remove_event(ServiceCompletion(self, self.served_packet.t_finish))
self.served_packet.pause_service()
self.server_busy = False
def remove_oldest_packet(self):
# removes the oldest packet from server
if self.served_packet == None:
if self.buffer.is_empty():
raise RuntimeError("ERROR: buffer empty, cant remove the packet.")
else:
self.removed_packet = self.buffer.remove()
else:
if self.served_packet.served:
self.pause_service()
self.served_packet = None
if self.start_service():
self.event_chain.insert(ServiceCompletion(self.slicesim, self.served_packet.t_finish))
else:
self.served_packet = None
self.server_state.packet_removed()