Files
wren/test/benchmark/delta_blue.py
Bill Quith 0fa16a20ec Fix deprecated Python timing in benchmark & give more error info. (#844)
- Note: process_time gives CPU time used and perf_counter is absolute time used.
- Looks to have noise of about 1-2%.
2021-01-30 21:40:20 -08:00

637 lines
17 KiB
Python

"""
deltablue.py
============
Ported for the PyPy project.
This implementation of the DeltaBlue benchmark was directly ported
from the `V8's source code`_, which was in turn derived
from the Smalltalk implementation by John Maloney and Mario
Wolczko. The original Javascript implementation was licensed under the GPL.
It's been updated in places to be more idiomatic to Python (for loops over
collections, a couple magic methods, ``OrderedCollection`` being a list & things
altering those collections changed to the builtin methods) but largely retains
the layout & logic from the original. (Ugh.)
.. _`V8's source code`: (http://code.google.com/p/v8/source/browse/branches/bleeding_edge/benchmarks/deltablue.js)
From: https://gist.github.com/toastdriven/6408132
I (Bob Nystrom) tweaked it a bit more. It now prints some output just to be
sure it's doing the same work, and I use normal lists instead of wrapping it in
OrderedCollection.
"""
from __future__ import print_function
import time
__author__ = 'Daniel Lindsley'
__license__ = 'BSD'
class Strength(object):
REQUIRED = None
STRONG_PREFERRED = None
PREFERRED = None
STRONG_DEFAULT = None
NORMAL = None
WEAK_DEFAULT = None
WEAKEST = None
def __init__(self, strength, name):
super(Strength, self).__init__()
self.strength = strength
self.name = name
@classmethod
def stronger(cls, s1, s2):
return s1.strength < s2.strength
@classmethod
def weaker(cls, s1, s2):
return s1.strength > s2.strength
@classmethod
def weakest_of(cls, s1, s2):
if cls.weaker(s1, s2):
return s1
return s2
@classmethod
def strongest(cls, s1, s2):
if cls.stronger(s1, s2):
return s1
return s2
def next_weaker(self):
strengths = {
0: self.__class__.WEAKEST,
1: self.__class__.WEAK_DEFAULT,
2: self.__class__.NORMAL,
3: self.__class__.STRONG_DEFAULT,
4: self.__class__.PREFERRED,
# TODO: This looks like a bug in the original code. Shouldn't this be
# ``STRONG_PREFERRED? Keeping for porting sake...
5: self.__class__.REQUIRED,
}
return strengths[self.strength]
# This is a terrible pattern IMO, but true to the original JS implementation.
Strength.REQUIRED = Strength(0, "required")
Strength.STONG_PREFERRED = Strength(1, "strongPreferred")
Strength.PREFERRED = Strength(2, "preferred")
Strength.STRONG_DEFAULT = Strength(3, "strongDefault")
Strength.NORMAL = Strength(4, "normal")
Strength.WEAK_DEFAULT = Strength(5, "weakDefault")
Strength.WEAKEST = Strength(6, "weakest")
class Constraint(object):
def __init__(self, strength):
super(Constraint, self).__init__()
self.strength = strength
def add_constraint(self):
global planner
self.add_to_graph()
planner.incremental_add(self)
def satisfy(self, mark):
global planner
self.choose_method(mark)
if not self.is_satisfied():
if self.strength == Strength.REQUIRED:
print('Could not satisfy a required constraint!')
return None
self.mark_inputs(mark)
out = self.output()
overridden = out.determined_by
if overridden is not None:
overridden.mark_unsatisfied()
out.determined_by = self
if not planner.add_propagate(self, mark):
print('Cycle encountered')
out.mark = mark
return overridden
def destroy_constraint(self):
global planner
if self.is_satisfied():
planner.incremental_remove(self)
else:
self.remove_from_graph()
def is_input(self):
return False
class UrnaryConstraint(Constraint):
def __init__(self, v, strength):
super(UrnaryConstraint, self).__init__(strength)
self.my_output = v
self.satisfied = False
self.add_constraint()
def add_to_graph(self):
self.my_output.add_constraint(self)
self.satisfied = False
def choose_method(self, mark):
if self.my_output.mark != mark and \
Strength.stronger(self.strength, self.my_output.walk_strength):
self.satisfied = True
else:
self.satisfied = False
def is_satisfied(self):
return self.satisfied
def mark_inputs(self, mark):
# No-ops.
pass
def output(self):
# Ugh. Keeping it for consistency with the original. So much for
# "we're all adults here"...
return self.my_output
def recalculate(self):
self.my_output.walk_strength = self.strength
self.my_output.stay = not self.is_input()
if self.my_output.stay:
self.execute()
def mark_unsatisfied(self):
self.satisfied = False
def inputs_known(self, mark):
return True
def remove_from_graph(self):
if self.my_output is not None:
self.my_output.remove_constraint(self)
self.satisfied = False
class StayConstraint(UrnaryConstraint):
def __init__(self, v, string):
super(StayConstraint, self).__init__(v, string)
def execute(self):
# The methods, THEY DO NOTHING.
pass
class EditConstraint(UrnaryConstraint):
def __init__(self, v, string):
super(EditConstraint, self).__init__(v, string)
def is_input(self):
return True
def execute(self):
# This constraint also does nothing.
pass
class Direction(object):
# Hooray for things that ought to be structs!
NONE = 0
FORWARD = 1
BACKWARD = -1
class BinaryConstraint(Constraint):
def __init__(self, v1, v2, strength):
super(BinaryConstraint, self).__init__(strength)
self.v1 = v1
self.v2 = v2
self.direction = Direction.NONE
self.add_constraint()
def choose_method(self, mark):
if self.v1.mark == mark:
if self.v2.mark != mark and Strength.stronger(self.strength, self.v2.walk_strength):
self.direction = Direction.FORWARD
else:
self.direction = Direction.BACKWARD
if self.v2.mark == mark:
if self.v1.mark != mark and Strength.stronger(self.strength, self.v1.walk_strength):
self.direction = Direction.BACKWARD
else:
self.direction = Direction.NONE
if Strength.weaker(self.v1.walk_strength, self.v2.walk_strength):
if Strength.stronger(self.strength, self.v1.walk_strength):
self.direction = Direction.BACKWARD
else:
self.direction = Direction.NONE
else:
if Strength.stronger(self.strength, self.v2.walk_strength):
self.direction = Direction.FORWARD
else:
self.direction = Direction.BACKWARD
def add_to_graph(self):
self.v1.add_constraint(self)
self.v2.add_constraint(self)
self.direction = Direction.NONE
def is_satisfied(self):
return self.direction != Direction.NONE
def mark_inputs(self, mark):
self.input().mark = mark
def input(self):
if self.direction == Direction.FORWARD:
return self.v1
return self.v2
def output(self):
if self.direction == Direction.FORWARD:
return self.v2
return self.v1
def recalculate(self):
ihn = self.input()
out = self.output()
out.walk_strength = Strength.weakest_of(self.strength, ihn.walk_strength)
out.stay = ihn.stay
if out.stay:
self.execute()
def mark_unsatisfied(self):
self.direction = Direction.NONE
def inputs_known(self, mark):
i = self.input()
return i.mark == mark or i.stay or i.determined_by == None
def remove_from_graph(self):
if self.v1 is not None:
self.v1.remove_constraint(self)
if self.v2 is not None:
self.v2.remove_constraint(self)
self.direction = Direction.NONE
class ScaleConstraint(BinaryConstraint):
def __init__(self, src, scale, offset, dest, strength):
self.direction = Direction.NONE
self.scale = scale
self.offset = offset
super(ScaleConstraint, self).__init__(src, dest, strength)
def add_to_graph(self):
super(ScaleConstraint, self).add_to_graph()
self.scale.add_constraint(self)
self.offset.add_constraint(self)
def remove_from_graph(self):
super(ScaleConstraint, self).remove_from_graph()
if self.scale is not None:
self.scale.remove_constraint(self)
if self.offset is not None:
self.offset.remove_constraint(self)
def mark_inputs(self, mark):
super(ScaleConstraint, self).mark_inputs(mark)
self.scale.mark = mark
self.offset.mark = mark
def execute(self):
if self.direction == Direction.FORWARD:
self.v2.value = self.v1.value * self.scale.value + self.offset.value
else:
self.v1.value = (self.v2.value - self.offset.value) / self.scale.value
def recalculate(self):
ihn = self.input()
out = self.output()
out.walk_strength = Strength.weakest_of(self.strength, ihn.walk_strength)
out.stay = ihn.stay and self.scale.stay and self.offset.stay
if out.stay:
self.execute()
class EqualityConstraint(BinaryConstraint):
def execute(self):
self.output().value = self.input().value
class Variable(object):
def __init__(self, name, initial_value=0):
super(Variable, self).__init__()
self.name = name
self.value = initial_value
self.constraints = []
self.determined_by = None
self.mark = 0
self.walk_strength = Strength.WEAKEST
self.stay = True
def __repr__(self):
# To make debugging this beast from pdb easier...
return '<Variable: %s - %s>' % (
self.name,
self.value
)
def add_constraint(self, constraint):
self.constraints.append(constraint)
def remove_constraint(self, constraint):
self.constraints.remove(constraint)
if self.determined_by == constraint:
self.determined_by = None
class Planner(object):
def __init__(self):
super(Planner, self).__init__()
self.current_mark = 0
def incremental_add(self, constraint):
mark = self.new_mark()
overridden = constraint.satisfy(mark)
while overridden is not None:
overridden = overridden.satisfy(mark)
def incremental_remove(self, constraint):
out = constraint.output()
constraint.mark_unsatisfied()
constraint.remove_from_graph()
unsatisfied = self.remove_propagate_from(out)
strength = Strength.REQUIRED
# Do-while, the Python way.
repeat = True
while repeat:
for u in unsatisfied:
if u.strength == strength:
self.incremental_add(u)
strength = strength.next_weaker()
repeat = strength != Strength.WEAKEST
def new_mark(self):
self.current_mark += 1
return self.current_mark
def make_plan(self, sources):
mark = self.new_mark()
plan = Plan()
todo = sources
while len(todo):
c = todo.pop(0)
if c.output().mark != mark and c.inputs_known(mark):
plan.add_constraint(c)
c.output().mark = mark
self.add_constraints_consuming_to(c.output(), todo)
return plan
def extract_plan_from_constraints(self, constraints):
sources = []
for c in constraints:
if c.is_input() and c.is_satisfied():
sources.append(c)
return self.make_plan(sources)
def add_propagate(self, c, mark):
todo = []
todo.append(c)
while len(todo):
d = todo.pop(0)
if d.output().mark == mark:
self.incremental_remove(c)
return False
d.recalculate()
self.add_constraints_consuming_to(d.output(), todo)
return True
def remove_propagate_from(self, out):
out.determined_by = None
out.walk_strength = Strength.WEAKEST
out.stay = True
unsatisfied = []
todo = []
todo.append(out)
while len(todo):
v = todo.pop(0)
for c in v.constraints:
if not c.is_satisfied():
unsatisfied.append(c)
determining = v.determined_by
for c in v.constraints:
if c != determining and c.is_satisfied():
c.recalculate()
todo.append(c.output())
return unsatisfied
def add_constraints_consuming_to(self, v, coll):
determining = v.determined_by
cc = v.constraints
for c in cc:
if c != determining and c.is_satisfied():
# I guess we're just updating a reference (``coll``)? Seems
# inconsistent with the rest of the implementation, where they
# return the lists...
coll.append(c)
class Plan(object):
def __init__(self):
super(Plan, self).__init__()
self.v = []
def add_constraint(self, c):
self.v.append(c)
def __len__(self):
return len(self.v)
def __getitem__(self, index):
return self.v[index]
def execute(self):
for c in self.v:
c.execute()
# Main
total = 0
def chain_test(n):
"""
This is the standard DeltaBlue benchmark. A long chain of equality
constraints is constructed with a stay constraint on one end. An
edit constraint is then added to the opposite end and the time is
measured for adding and removing this constraint, and extracting
and executing a constraint satisfaction plan. There are two cases.
In case 1, the added constraint is stronger than the stay
constraint and values must propagate down the entire length of the
chain. In case 2, the added constraint is weaker than the stay
constraint so it cannot be accomodated. The cost in this case is,
of course, very low. Typical situations lie somewhere between these
two extremes.
"""
global planner
global total
planner = Planner()
prev, first, last = None, None, None
# We need to go up to n inclusively.
for i in range(n + 1):
name = "v%s" % i
v = Variable(name)
if prev is not None:
EqualityConstraint(prev, v, Strength.REQUIRED)
if i == 0:
first = v
if i == n:
last = v
prev = v
StayConstraint(last, Strength.STRONG_DEFAULT)
edit = EditConstraint(first, Strength.PREFERRED)
edits = []
edits.append(edit)
plan = planner.extract_plan_from_constraints(edits)
for i in range(100):
first.value = i
plan.execute()
total += int(last.value)
if last.value != i:
print("Chain test failed.")
def projection_test(n):
"""
This test constructs a two sets of variables related to each
other by a simple linear transformation (scale and offset). The
time is measured to change a variable on either side of the
mapping and to change the scale and offset factors.
"""
global planner
global total
planner = Planner()
scale = Variable("scale", 10)
offset = Variable("offset", 1000)
src, dest = None, None
dests = []
for i in range(n):
src = Variable("src%s" % i, i)
dst = Variable("dst%s" % i, i)
dests.append(dst)
StayConstraint(src, Strength.NORMAL)
ScaleConstraint(src, scale, offset, dst, Strength.REQUIRED)
change(src, 17)
total += int(dst.value)
if dst.value != 1170:
print("Projection 1 failed")
change(dst, 1050)
total += int(src.value)
if src.value != 5:
print("Projection 2 failed")
change(scale, 5)
for i in range(n - 1):
total += int(dests[i].value)
if dests[i].value != (i * 5 + 1000):
print("Projection 3 failed")
change(offset, 2000)
for i in range(n - 1):
total += int(dests[i].value)
if dests[i].value != (i * 5 + 2000):
print("Projection 4 failed")
def change(v, new_value):
global planner
edit = EditConstraint(v, Strength.PREFERRED)
edits = []
edits.append(edit)
plan = planner.extract_plan_from_constraints(edits)
for i in range(10):
v.value = new_value
plan.execute()
edit.destroy_constraint()
# HOORAY FOR GLOBALS... Oh wait.
# In spirit of the original, we'll keep it, but ugh.
planner = None
def delta_blue():
global total
start = time.process_time()
for i in range(40):
chain_test(100)
projection_test(100)
print(total)
print("elapsed: " + str(time.process_time() - start))
if __name__ == '__main__':
delta_blue()