def test_concurrent_tabu_samples(self):
t1 = hybrid.TabuProblemSampler(timeout=1000)
t2 = hybrid.TabuProblemSampler(timeout=2000)
workflow = hybrid.Parallel(t1, t2)
bqm = dimod.BinaryQuadraticModel({'a': 1}, {}, 0, 'BINARY')
state = hybrid.State.from_problem(bqm)
with self.assertRuntimeWithin(1900, 2500):
workflow.run(state).result()
def test_sa_concurrency(self):
params = dict(num_reads=1, num_sweeps=1000000)
# serial and parallel SA runs
s = (hybrid.SimulatedAnnealingProblemSampler(**params)
| hybrid.SimulatedAnnealingProblemSampler(**params))
p = hybrid.Parallel(hybrid.SimulatedAnnealingProblemSampler(**params),
hybrid.SimulatedAnnealingProblemSampler(**params))
bqm = dimod.generators.uniform(graph=1, vartype=dimod.SPIN)
state = hybrid.State.from_problem(bqm)
# average wall clock workflow runtime over `repeat` runs
def time_workflow(workflow, state, repeat=10):
with hybrid.tictoc() as timer:
for _ in range(repeat):
workflow.run(state).result()
return timer.dt / repeat
# measure speed-up of parallel SA runs over sequential
# NOTE: relatively weak lower bound on speedup was chosen so we don't
# fail on the unreliable/inconsistent CI VMs, but to verify some level
# of concurrency does exist
if os.name == 'nt':
# appveyor sucks
minimally_acceptable_speedup = 1.0
else:
minimally_acceptable_speedup = 1.5
# NOTE: on average, the observed speed-up is between 1.5x and 2x, but
# it's highly dependant on the system load and availability of threads.
# That's why we do multiple runs, and bail out on the first good speedup
speedups = []
best_speedup = 0
for run in range(250): # alternatively, run for up to X sec
t_s = time_workflow(s, state)
t_p = time_workflow(p, state)
speedup = t_s / t_p
speedups.append(speedup)
best_speedup = max(best_speedup, speedup)
if best_speedup > minimally_acceptable_speedup:
break
info = "best speed-up of {} achieved within {} runs: {!r}".format(
best_speedup, run + 1, speedups)
self.assertGreaterEqual(best_speedup, minimally_acceptable_speedup,
info)
def test_concurrent_sa_samples(self):
s1 = hybrid.SimulatedAnnealingProblemSampler(num_reads=1000, sweeps=10000)
s2 = hybrid.SimulatedAnnealingProblemSampler(num_reads=1000, sweeps=10000)
p = hybrid.Parallel(s1, s2)
bqm = dimod.BinaryQuadraticModel({'a': 1}, {}, 0, 'BINARY')
state = hybrid.State.from_problem(bqm)
def time_runnable(runnable, init):
runnable.run(init).result()
return sum(runnable.timers['dispatch.next'])
t_s1 = time_runnable(s1, state)
t_s2 = time_runnable(s2, state)
t_p = time_runnable(p, state)
# parallel execution must not be slower than the longest running branch + 75%
# NOTE: the extremely weak upper bound was chosen so we don't fail on the
# unreliable/inconsistent CI VMs, and yet to show some concurrency does exist
t_expected_max = max(t_s1, t_s2) * 1.75
self.assertLess(t_p, t_expected_max)
problem = sys.argv[1]
with open(problem) as fp:
bqm = dimod.BinaryQuadraticModel.from_coo(fp)
# construct a Dialectic Search workflow
generate_antithesis = (hybrid.IdentityDecomposer()
| hybrid.RandomSubproblemSampler()
| hybrid.SplatComposer()
| hybrid.TabuProblemSampler())
generate_synthesis = (hybrid.GreedyPathMerge() | hybrid.TabuProblemSampler())
tracker = hybrid.TrackMin()
local_update = hybrid.LoopWhileNoImprovement(
hybrid.Parallel(hybrid.Identity(), generate_antithesis)
| generate_synthesis | tracker,
max_tries=10)
global_update = hybrid.Loop(generate_antithesis | local_update, max_iter=10)
# run the workflow
init_state = hybrid.State.from_sample(hybrid.min_sample(bqm), bqm)
final_state = global_update.run(init_state).result()
# show execution profile
hybrid.profiling.print_counters(global_update)
# show results
print("Solution: sample={.samples.first}".format(tracker.best))
def merge_substates(_, substates):
a, b = substates
return a.updated(
subsamples=hybrid.hstack_samplesets(a.subsamples, b.subsamples))
subproblems = hybrid.Unwind(
hybrid.EnergyImpactDecomposer(size=50, rolling_history=0.15))
qpu = hybrid.Map(hybrid.QPUSubproblemAutoEmbeddingSampler()) | hybrid.Reduce(
hybrid.Lambda(merge_substates)) | hybrid.SplatComposer()
random = hybrid.Map(hybrid.RandomSubproblemSampler()) | hybrid.Reduce(
hybrid.Lambda(merge_substates)) | hybrid.SplatComposer()
subsampler = hybrid.Parallel(qpu, random, endomorphic=False) | hybrid.ArgMin()
iteration = hybrid.Race(hybrid.InterruptableTabuSampler(),
subproblems | subsampler) | hybrid.ArgMin()
main = hybrid.Loop(iteration, max_iter=10, convergence=3)
# run the workflow
init_state = hybrid.State.from_sample(hybrid.min_sample(bqm), bqm)
solution = main.run(init_state).result()
# show execution profile
hybrid.profiling.print_counters(main)
# show results
print("Solution: sample={.samples.first}".format(solution))
def merge_substates(_, substates):
a, b = substates
return a.updated(
subsamples=hybrid.hstack_samplesets(a.subsamples, b.subsamples))
subproblems = hybrid.Unwind(
hybrid.EnergyImpactDecomposer(size=50, rolling_history=0.15))
qpu = hybrid.Map(hybrid.QPUSubproblemAutoEmbeddingSampler()) | hybrid.Reduce(
hybrid.Lambda(merge_substates)) | hybrid.SplatComposer()
random = hybrid.Map(hybrid.RandomSubproblemSampler()) | hybrid.Reduce(
hybrid.Lambda(merge_substates)) | hybrid.SplatComposer()
subsampler = hybrid.Parallel(qpu, random) | hybrid.ArgMin()
iteration = hybrid.Race(
hybrid.InterruptableTabuSampler(),
subproblems | subsampler) | hybrid.ArgMin() | hybrid.TrackMin(output=True)
main = hybrid.Loop(iteration, max_iter=10, convergence=3)
# run the workflow
init_state = hybrid.State.from_sample(hybrid.min_sample(bqm), bqm)
solution = main.run(init_state).result()
# show execution profile
hybrid.profiling.print_counters(main)
# show results