The code is given below. Actually, I have two nodes 0 and 1 where server capacities are 5 and 7 respectively. The servers are unavailable before 9AM (540 mins from midnight) and after 6 PM everyday. I am trying to create the unavailability using timeout but not working. I still do see items are entering nodes 0 and 1 beyond 6 PM on the second day (that is after 2520 minutes). Can't figure out the mistake. Thanks a lot!
import numpy as np
import simpy
def interarrival():
return(np.random.exponential(20))
def servicetime():
return(np.random.exponential(60))
def servicing(env, servers_1):
i = 0
while(True):
i = i+1
yield env.timeout(interarrival())
print("Customer "+str(i)+ " arrived in the process at "+str(env.now))
state = 0
env.process(items(env, i, servers_array, state))
def items(env, customer_id, servers_array, state):
with servers_array[state].request() as request:
yield request
t_arrival = env.now
print("Customer "+str(customer_id)+ " arrived in "+str(state)+ " at "+str(t_arrival))
yield env.timeout(servicetime())
t_depart = env.now
print("Customer "+str(customer_id)+ " departed from "+str(state)+ " at "+str(t_depart))
if (state == 1):
print("Customer exits")
else:
state = 1
env.process(items(env, customer_id, servers_array, state))
def delay(env, servers_array):
while(True):
#print(servers_array[0].request())
if (env.now%1440 >= 540 and env.now%1440 < 1080):
yield env.timeout(1080 - env.now%1440)
else:
print(str(env.now), "at resources will be blocked")
resource_unavailability_dict = dict()
resource_unavailability_dict[0] = []
resource_unavailability_dict[1] = []
for nodes in resource_unavailability_dict:
for _ in range(servers_array[nodes].capacity):
resource_unavailability_dict[nodes].append(servers_array[nodes].request())
print(resource_unavailability_dict)
for nodes in resource_unavailability_dict:
yield env.all_of(resource_unavailability_dict[nodes])
if (env.now < 540):
yield env.timeout(540)
else:
yield env.timeout((int(env.now/1440)+1)*1440+540 - env.now)
for nodes in resource_unavailability_dict:
for request in resource_unavailability_dict[nodes]:
servers_array[nodes].release(request)
print(str(env.now), "resources are released")
env = simpy.Environment()
servers_array = []
servers_array.append(simpy.Resource(env, capacity = 5))
servers_array.append(simpy.Resource(env, capacity = 7))
env.process(servicing(env, servers_array))
env.process(delay(env,servers_array))
env.run(until=2880)
Think I found it. you are yielding to a int expressing, I think you need to wrap you int expression with a timeout event
try changing
yield(1080 - env.now%1440)
to
yield env.timeout(1080 - env.now%1440)
in def delay, I do not know what happens if your int expression passes a negative value to timeout. you may need to add a check for that