def test_group_value(self):
"""Test that the value of a replica group is calculated correctly.
Group value is calculated by the following formula (from the paper):
sum(NOR) / sum(sizes) + sum(NOR_FSTI) / FSTI +
1 / (now - avg(last_req_time))
"""
sim = Mock(spec=self._make_sim())
sim.fsti = 10
sim.now = 4
node = self._make_instance('node_1', 1000, sim)
replica_group = [
self._make_replica('replica_1', size=200),
self._make_replica('replica_2', size=400),
self._make_replica('replica_3', size=900),
]
stats_1 = Mock(nor=0, lrt=0)
stats_1.nor_fsti.return_value = 0
node._replica_stats['replica_1'] = stats_1
stats_2 = Mock(nor=0, lrt=0)
stats_2.nor_fsti.return_value = 0
node._replica_stats['replica_2'] = stats_2
stats_3 = Mock(nor=0, lrt=0)
stats_3.nor_fsti.return_value = 0
node._replica_stats['replica_3'] = stats_3
self.assertAlmostEqual(node._GV(replica_group), 0.25)
stats_1.nor = 15
self.assertAlmostEqual(node._GV(replica_group), 0.26)
stats_2.nor = 45
self.assertAlmostEqual(node._GV(replica_group), 0.29)
replica_group[2]._size = 2400
self.assertAlmostEqual(node._GV(replica_group), 0.27)
stats_1.nor_fsti.return_value = 5
self.assertAlmostEqual(node._GV(replica_group), 0.77)
stats_2.nor_fsti.return_value = 20
self.assertAlmostEqual(node._GV(replica_group), 2.77)
stats_1.lrt = 1
stats_2.lrt = 2
stats_3.lrt = 3
self.assertAlmostEqual(node._GV(replica_group), 3.02)
sim.now = 7
self.assertAlmostEqual(node._GV(replica_group), 2.72)
def test_replica_value(self):
"""Test that the value of a replica is calculated correctly.
Replica value is calculated by the following formula (from the paper):
NOR / replica.size + NOR_FSTI / FSTI +
1 / (now - repl_last_req_time)
"""
sim = Mock(spec=self._make_sim())
sim.fsti = 10
sim.now = 4
replica = self._make_replica('replica_1', size=200)
node = self._make_instance('node_1', 1000, sim)
repl_stats = Mock(nor=0, lrt=0)
repl_stats.nor_fsti.return_value = 0
node._replica_stats['replica_1'] = repl_stats
self.assertAlmostEqual(node._RV(replica), 0.25)
repl_stats.nor = 20
self.assertAlmostEqual(node._RV(replica), 0.35)
replica._size = 50
self.assertAlmostEqual(node._RV(replica), 0.65)
repl_stats.nor_fsti.return_value = 15
self.assertAlmostEqual(node._RV(replica), 2.15)
repl_stats.lrt = 3
self.assertAlmostEqual(node._RV(replica), 2.90)
sim.now = 8
self.assertAlmostEqual(node._RV(replica), 2.10)