class RoutineWorkload(Workload):
"""
A routine workload generates accesses according to the following params:
- A normal distribution time between accesses
- A probability of reads (vs. writes)
- A probability of switching objects (vs. continuing with current)
This is the simplest workload that is completely implemented.
"""
def __init__(self, sim, **kwargs):
"""
Initialize workload probabilities and distributions before passing
all optional keyword arguments to the super class.
"""
# Distribution for whether or not to change objects
self.do_object = Bernoulli(
kwargs.pop('object_prob', settings.simulation.object_prob))
self.do_read = Bernoulli(
kwargs.pop('read_prob', settings.simulation.read_prob))
# Interval distribution for the wait (in ms) to the next access.
self.next_access = BoundedNormal(
kwargs.pop('access_mean', settings.simulation.access_mean),
kwargs.pop('access_stddev', settings.simulation.access_stddev),
floor=1.0,
)
# Initialize the Workload
super(RoutineWorkload, self).__init__(sim, **kwargs)
# If current is None, update the state of the workload:
if self.current is None: self.update()
def update(self, **kwargs):
"""
Uses the do_object distribution to determine whether or not to change
the currently accessed object to a new object.
"""
# Do we switch the current object?
if self.current is None or self.do_object.get():
if len(self.objects) == 1:
# There is only one choice, no switching!
self.current = self.objects[0]
else:
# Randomly select an object that is not the current object.
self.current = Discrete([
obj for obj in self.objects if obj != self.current
]).get()
# Call to the super update method
super(RoutineWorkload, self).update(**kwargs)
def wait(self):
"""
Utilizes the bounded normal distribution to return the wait (in
milliseconds) until the next access.
"""
return self.next_access.get()
def access(self):
"""
Utilizes the do_read distribution to determine whether or not to
issue a write or a read access, and calls the device method for it.
"""
# Make sure that there is a device to write to!
if not self.device:
raise WorkloadException(
"No device specified to trigger the access on!")
# Make sure that there is a current object to write!
if not self.current:
raise WorkloadException(
"No object specified as currently open on the workload!")
# Determine if we are reading or writing.
access = READ if self.do_read.get() else WRITE
# Log the results on the timeseries for the access.
self.sim.results.update(
access,
(self.device.id, self.location, self.current, self.env.now))
if access == READ:
# Read the latest version of the current object
return self.device.read(self.current)
if access == WRITE:
# Write to the current version (e.g. call nextv)
return self.device.write(self.current)
class RoutineWorkload(Workload):
"""
A routine workload generates accesses according to the following params:
- A normal distribution time between accesses
- A probability of reads (vs. writes)
- A probability of switching objects (vs. continuing with current)
This is the simplest workload that is completely implemented.
"""
def __init__(self, sim, **kwargs):
"""
Initialize workload probabilities and distributions before passing
all optional keyword arguments to the super class.
"""
# Distribution for whether or not to change objects
self.do_object = Bernoulli(kwargs.pop("object_prob", settings.simulation.object_prob))
self.do_read = Bernoulli(kwargs.pop("read_prob", settings.simulation.read_prob))
# Interval distribution for the wait (in ms) to the next access.
self.next_access = BoundedNormal(
kwargs.pop("access_mean", settings.simulation.access_mean),
kwargs.pop("access_stddev", settings.simulation.access_stddev),
floor=1.0,
)
# Initialize the Workload
super(RoutineWorkload, self).__init__(sim, **kwargs)
# If current is None, update the state of the workload:
if self.current is None:
self.update()
def update(self, **kwargs):
"""
Uses the do_object distribution to determine whether or not to change
the currently accessed object to a new object.
"""
# Do we switch the current object?
if self.current is None or self.do_object.get():
if len(self.objects) == 1:
# There is only one choice, no switching!
self.current = self.objects[0]
else:
# Randomly select an object that is not the current object.
self.current = Discrete([obj for obj in self.objects if obj != self.current]).get()
# Call to the super update method
super(RoutineWorkload, self).update(**kwargs)
def wait(self):
"""
Utilizes the bounded normal distribution to return the wait (in
milliseconds) until the next access.
"""
return self.next_access.get()
def access(self):
"""
Utilizes the do_read distribution to determine whether or not to
issue a write or a read access, and calls the device method for it.
"""
# Make sure that there is a device to write to!
if not self.device:
raise WorkloadException("No device specified to trigger the access on!")
# Make sure that there is a current object to write!
if not self.current:
raise WorkloadException("No object specified as currently open on the workload!")
# Determine if we are reading or writing.
access = READ if self.do_read.get() else WRITE
# Log the results on the timeseries for the access.
self.sim.results.update(access, (self.device.id, self.location, self.current, self.env.now))
if access == READ:
# Read the latest version of the current object
return self.device.read(self.current)
if access == WRITE:
# Write to the current version (e.g. call nextv)
return self.device.write(self.current)
class OutageGenerator(NamedProcess):
"""
A process that causes outages to occur across the wide or local area or
across both areas, or to occur for leaders only. Outages are generated on
a collection of connections, usually collected together based on the
connection type. The outages script is run as follows in the simulation:
- determine the probability of online vs. outage
- use the normal distribution of online/outage to determine duration
- cause outage if outage, wait until duration is over.
- repeat from the first step.
Outages can also do more than cut the connection, they can also vary the
latency for that connection by changing the network parameters.
"""
def __init__(self, sim, connections, **kwargs):
"""
Initialize the workload with the simulation (containing both the
environment and the topology for work), the set of connections to
cause outages for as a group, and any additional arguments.
"""
self.sim = sim
self.connections = connections
self.do_outage = Bernoulli(kwargs.pop('outage_prob', settings.simulation.outage_prob))
# NOTE: This will not call any methods on the connections (on purpose)
self._state = ONLINE
# Distribution of outage duration
self.outage_duration = BoundedNormal(
kwargs.pop('outage_mean', settings.simulation.outage_mean),
kwargs.pop('outage_stddev', settings.simulation.outage_stddev),
floor = 10.0,
)
# Distribution of online duration
self.online_duration = BoundedNormal(
kwargs.pop('online_mean', settings.simulation.online_mean),
kwargs.pop('online_stddev', settings.simulation.online_stddev),
floor = 10.0,
)
# Initialize the Process
super(OutageGenerator, self).__init__(sim.env)
@setter
def connections(self, value):
"""
Allows passing a single connection instance or multiple.
"""
if not isinstance(value, (tuple, list)):
value = (value,)
return tuple(value)
@setter
def state(self, state):
"""
When the state is set on the outage generator, update connections.
"""
if state == ONLINE:
self.update_online_state()
elif state == OUTAGE:
self.update_outage_state()
else:
raise OutagesException(
"Unknown state: '{}' set either {} or {}".format(
state, ONLINE, OUTAGE
)
)
return state
def update_online_state(self):
"""
Sets the state of the generator to online.
NOTE - should not be called by clients but can be subclassed!
"""
# If we were previously offline:
if self.state == OUTAGE:
for conn in self.connections:
conn.up()
self.sim.logger.debug(
"{} is now online".format(conn)
)
def update_outage_state(self):
"""
Sets the state of the generator to outage.
NOTE - should not be called by clients but can be subclassed!
"""
# If we were previously online:
if self.state == ONLINE:
for conn in self.connections:
conn.down()
self.sim.logger.debug(
"{} is now offline".format(conn)
)
def duration(self):
"""
Returns the duration of the current state in milliseconds.
"""
if self.state == ONLINE:
return self.online_duration.get()
if self.state == OUTAGE:
return self.outage_duration.get()
def update(self):
"""
Updates the state of the connections according to the outage
probability. This method should be called routinely according to the
outage and online duration distributions.
"""
if self.do_outage.get():
self.state = OUTAGE
else:
self.state = ONLINE
def run(self):
"""
The action that generates outages on the passed in set of connections.
"""
while True:
# Get the duration of the current state
duration = self.duration()
# Log (info) the outage/online state and duration
self.sim.logger.info(
"{} connections {} for {}".format(
len(self.connections), self.state,
humanizedelta(milliseconds=duration)
)
)
# Wait for the duration
yield self.env.timeout(duration)
# Update the state of the outage
self.update()
def __str__(self):
"""
String representation of the outage generator.
"""
return "{}: {} connections {}".format(
self.name, len(self.connections), self.state
)
class OutageGenerator(NamedProcess):
"""
A process that causes outages to occur across the wide or local area or
across both areas, or to occur for leaders only. Outages are generated on
a collection of connections, usually collected together based on the
connection type. The outages script is run as follows in the simulation:
- determine the probability of online vs. outage
- use the normal distribution of online/outage to determine duration
- cause outage if outage, wait until duration is over.
- repeat from the first step.
Outages can also do more than cut the connection, they can also vary the
latency for that connection by changing the network parameters.
"""
def __init__(self, sim, connections, **kwargs):
"""
Initialize the workload with the simulation (containing both the
environment and the topology for work), the set of connections to
cause outages for as a group, and any additional arguments.
"""
self.sim = sim
self.connections = connections
self.do_outage = Bernoulli(
kwargs.pop('outage_prob', settings.simulation.outage_prob))
# NOTE: This will not call any methods on the connections (on purpose)
self._state = ONLINE
# Distribution of outage duration
self.outage_duration = BoundedNormal(
kwargs.pop('outage_mean', settings.simulation.outage_mean),
kwargs.pop('outage_stddev', settings.simulation.outage_stddev),
floor=10.0,
)
# Distribution of online duration
self.online_duration = BoundedNormal(
kwargs.pop('online_mean', settings.simulation.online_mean),
kwargs.pop('online_stddev', settings.simulation.online_stddev),
floor=10.0,
)
# Initialize the Process
super(OutageGenerator, self).__init__(sim.env)
@setter
def connections(self, value):
"""
Allows passing a single connection instance or multiple.
"""
if not isinstance(value, (tuple, list)):
value = (value, )
return tuple(value)
@setter
def state(self, state):
"""
When the state is set on the outage generator, update connections.
"""
if state == ONLINE:
self.update_online_state()
elif state == OUTAGE:
self.update_outage_state()
else:
raise OutagesException(
"Unknown state: '{}' set either {} or {}".format(
state, ONLINE, OUTAGE))
return state
def update_online_state(self):
"""
Sets the state of the generator to online.
NOTE - should not be called by clients but can be subclassed!
"""
# If we were previously offline:
if self.state == OUTAGE:
for conn in self.connections:
conn.up()
self.sim.logger.debug("{} is now online".format(conn))
def update_outage_state(self):
"""
Sets the state of the generator to outage.
NOTE - should not be called by clients but can be subclassed!
"""
# If we were previously online:
if self.state == ONLINE:
for conn in self.connections:
conn.down()
self.sim.logger.debug("{} is now offline".format(conn))
def duration(self):
"""
Returns the duration of the current state in milliseconds.
"""
if self.state == ONLINE:
return self.online_duration.get()
if self.state == OUTAGE:
return self.outage_duration.get()
def update(self):
"""
Updates the state of the connections according to the outage
probability. This method should be called routinely according to the
outage and online duration distributions.
"""
if self.do_outage.get():
self.state = OUTAGE
else:
self.state = ONLINE
def run(self):
"""
The action that generates outages on the passed in set of connections.
"""
while True:
# Get the duration of the current state
duration = self.duration()
# Log (info) the outage/online state and duration
self.sim.logger.info("{} connections {} for {}".format(
len(self.connections), self.state,
humanizedelta(milliseconds=duration)))
# Wait for the duration
yield self.env.timeout(duration)
# Update the state of the outage
self.update()
def __str__(self):
"""
String representation of the outage generator.
"""
return "{}: {} connections {}".format(self.name, len(self.connections),
self.state)