x/terracotta
Code Issues Proposed changes

Added a new overload detection algorithm: last_n_average_threshold

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This commit is contained in:
Anton Beloglazov 2012-10-30 12:35:45 +11:00
parent c2442ae1fb
commit e53867f14c
2 changed files with 94 additions and 7 deletions
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45
neat/locals/overload/trivial.py
View File

@ -62,6 +62,29 @@ def threshold_factory(time_step, migration_time, params):
{})
@contract
def last_n_average_threshold_factory(time_step, migration_time, params):
""" Creates the averaging CPU utilization threshold algorithm.
:param time_step: The length of the simulation time step in seconds.
:type time_step: int,>=0
:param migration_time: The VM migration time in time seconds.
:type migration_time: float,>=0
:param params: A dictionary containing the algorithm's parameters.
:type params: dict(str: *)
:return: A function implementing the averaging threshold algorithm.
:rtype: function
"""
return lambda utilization, state=None: (
last_n_average_threshold(params['threshold'],
params['n'],
utilization),
{})
@contract
def threshold(threshold, utilization):
""" The static CPU utilization threshold algorithm.
@ -78,3 +101,25 @@ def threshold(threshold, utilization):
if utilization:
return utilization[-1] > threshold
return False
@contract
def last_n_average_threshold(threshold, n, utilization):
""" The averaging CPU utilization threshold algorithm.
:param threshold: The threshold on the CPU utilization.
:type threshold: float,>=0
:param n: The number of last CPU utilization values to average.
:type n: int,>0
:param utilization: The history of the host's CPU utilization.
:type utilization: list(float)
:return: The decision of the algorithm.
:rtype: bool
"""
if utilization:
utilization = utilization[-n:]
return sum(utilization) / len(utilization) > threshold
return False

56
tests/locals/overload/test_trivial.py
View File

@ -33,13 +33,6 @@ class Trivial(TestCase):
{'threshold': 0.5})
assert alg(utilization) == (False, {})
def test_threshold(self):
self.assertTrue(trivial.threshold(0.5, [0.9, 0.8, 1.1, 1.2, 1.3]))
self.assertTrue(trivial.threshold(0.5, [0.9, 0.8, 1.1, 1.2, 0.6]))
self.assertFalse(trivial.threshold(0.5, [0.9, 0.8, 1.1, 1.2, 0.5]))
self.assertFalse(trivial.threshold(0.5, [0.9, 0.8, 1.1, 1.2, 0.3]))
self.assertFalse(trivial.threshold(0.5, []))
def test_threshold_factory(self):
alg = trivial.threshold_factory(300, 20., {'threshold': 0.5})
self.assertEquals(alg([0.9, 0.8, 1.1, 1.2, 1.3]), (True, {}))
@ -47,3 +40,52 @@ class Trivial(TestCase):
self.assertEquals(alg([0.9, 0.8, 1.1, 1.2, 0.5]), (False, {}))
self.assertEquals(alg([0.9, 0.8, 1.1, 1.2, 0.3]), (False, {}))
self.assertEquals(alg([]), (False, {}))
def test_last_n_average_threshold_factory(self):
alg = trivial.last_n_average_threshold_factory(
300, 20., {'threshold': 0.5, 'n': 1})
self.assertEquals(alg([0.9, 0.8, 1.1, 1.2, 1.3]), (True, {}))
self.assertEquals(alg([0.9, 0.8, 1.1, 1.2, 0.6]), (True, {}))
self.assertEquals(alg([0.9, 0.8, 1.1, 1.2, 0.5]), (False, {}))
self.assertEquals(alg([0.9, 0.8, 1.1, 1.2, 0.3]), (False, {}))
self.assertEquals(alg([]), (False, {}))
alg = trivial.last_n_average_threshold_factory(
300, 20., {'threshold': 0.5, 'n': 2})
self.assertEquals(alg([0.9, 0.8, 1.1, 1.2, 1.3]), (True, {}))
self.assertEquals(alg([0.9, 0.8, 1.1, 1.2, 0.6]), (True, {}))
self.assertEquals(alg([0.9, 0.8, 1.1, 1.2, 0.4]), (True, {}))
self.assertEquals(alg([0.9, 0.8, 1.1, 0.4, 0.5]), (False, {}))
self.assertEquals(alg([0.9, 0.8, 1.1, 0.2, 0.3]), (False, {}))
self.assertEquals(alg([]), (False, {}))
def test_threshold(self):
self.assertTrue(trivial.threshold(0.5, [0.9, 0.8, 1.1, 1.2, 1.3]))
self.assertTrue(trivial.threshold(0.5, [0.9, 0.8, 1.1, 1.2, 0.6]))
self.assertFalse(trivial.threshold(0.5, [0.9, 0.8, 1.1, 1.2, 0.5]))
self.assertFalse(trivial.threshold(0.5, [0.9, 0.8, 1.1, 1.2, 0.3]))
self.assertFalse(trivial.threshold(0.5, []))
def test_last_n_average_threshold(self):
self.assertTrue(trivial.last_n_average_threshold(
0.5, 1, [0.9, 0.8, 1.1, 1.2, 1.3]))
self.assertTrue(trivial.last_n_average_threshold(
0.5, 1, [0.9, 0.8, 1.1, 1.2, 0.6]))
self.assertFalse(trivial.last_n_average_threshold(
0.5, 1, [0.9, 0.8, 1.1, 1.2, 0.5]))
self.assertFalse(trivial.last_n_average_threshold(
0.5, 1, [0.9, 0.8, 1.1, 1.2, 0.3]))
self.assertFalse(trivial.last_n_average_threshold(
0.5, 1, []))
self.assertTrue(trivial.last_n_average_threshold(
0.5, 2, [0.9, 0.8, 1.1, 1.2, 1.3]))
self.assertTrue(trivial.last_n_average_threshold(
0.5, 2, [0.9, 0.8, 1.1, 1.2, 0.6]))
self.assertTrue(trivial.last_n_average_threshold(
0.5, 2, [0.9, 0.8, 1.1, 1.2, 0.4]))
self.assertFalse(trivial.last_n_average_threshold(
0.5, 2, [0.9, 0.8, 1.1, 0.4, 0.5]))
self.assertFalse(trivial.last_n_average_threshold(
0.5, 2, [0.9, 0.8, 1.1, 0.2, 0.3]))
self.assertFalse(trivial.last_n_average_threshold(0.5, 2, []))