From b0c6c6dbac234ef8726f6f9c5f8a93d15944933a Mon Sep 17 00:00:00 2001
From: Dominic Kempf <dominic.kempf@iwr.uni-heidelberg.de>
Date: Mon, 12 Feb 2018 14:39:36 +0100
Subject: [PATCH] Rename optimization functions to levelx_...
We will need even more "levels" in the near future
---
python/dune/perftool/sumfact/vectorization.py | 125 ++++++++++--------
1 file changed, 68 insertions(+), 57 deletions(-)
diff --git a/python/dune/perftool/sumfact/vectorization.py b/python/dune/perftool/sumfact/vectorization.py
index 690a1c0b..95286389 100644
--- a/python/dune/perftool/sumfact/vectorization.py
+++ b/python/dune/perftool/sumfact/vectorization.py
@@ -172,59 +172,55 @@ def decide_vectorization_strategy():
logger.debug("decide_vectorization_strategy: Found {} active sum factorization nodes"
.format(len(active_sumfacts)))
- # Find the best vectorization strategy by using a costmodel
- width = get_vcl_type_size(dtype_floatingpoint())
-
#
- # Optimize over all the possible quadrature point tuples
+ # Find the best vectorization strategy by using a costmodel
#
- quad_points = [quadrature_points_per_direction()]
- if get_form_option("vectorization_allow_quadrature_changes"):
- sf = next(iter(active_sumfacts))
- depth = 1
- while depth <= width:
- i = 0 if sf.matrix_sequence[0].face is None else 1
- quad = list(quadrature_points_per_direction())
- quad[i] = round_to_multiple(quad[i], depth)
- quad_points.append(tuple(quad))
- depth = depth * 2
- quad_points = list(set(quad_points))
-
- if get_form_option("vectorization_strategy") == "fromlist":
- # This is a bit special and does not follow the minimization procedure at all
-
- def _choose_strategy_from_list(stage1_sumfacts):
- strategy = 0
- for qp in quad_points:
- for strat in fixed_quad_vectorization_opportunity_generator(frozenset(stage1_sumfacts), width, qp):
- if strategy == int(get_form_option("vectorization_list_index")):
- # Output the strategy and its cost into a separate file
- if get_global_context_value("form_type") == "jacobian_apply":
- with open("strategycosts.csv", "a") as f:
- f.write("{} {}\n".format(strategy, strategy_cost((qp, strat))))
- return qp, strat
- strategy = strategy + 1
-
- raise PerftoolVectorizationError("Specified vectorization list index '{}' was too high!".format(get_form_option("vectorization_list_index")))
-
- s1_sumfacts = frozenset(sf for sf in active_sumfacts if sf.stage == 1)
-
- total = sum(len([s for s in fixed_quad_vectorization_opportunity_generator(frozenset(s1_sumfacts), width, qp)]) for qp in quad_points)
- print("'fromlist' vectorization is attempting to pick #{} of {} strategies...".format(int(get_form_option("vectorization_list_index")),
- total))
- qp, sfdict = _choose_strategy_from_list(s1_sumfacts)
-
- keys = frozenset(sf.input_key for sf in active_sumfacts if sf.stage != 1)
- for key in keys:
- key_sumfacts = frozenset(sf for sf in active_sumfacts if sf.input_key == key)
- minimum = min(fixed_quad_vectorization_opportunity_generator(key_sumfacts, width, qp),
- key=fixedqp_strategy_costfunction(qp))
- sfdict = add_to_frozendict(sfdict, minimum)
- else:
- # Find the minimum cost strategy between all the quadrature point tuples
- optimal_strategies = {qp: fixed_quadrature_optimal_vectorization(active_sumfacts, width, qp) for qp in quad_points}
- qp = min(optimal_strategies, key=lambda qp: strategy_cost((qp, optimal_strategies[qp])))
- sfdict = optimal_strategies[qp]
+ # Note that this optimization procedure uses a hierarchic approach to bypass
+ # the problems of unfavorable complexity of the set of all possible vectorization
+ # opportunities. Optimizations are performed at different levels (you find these
+ # levels in the function names implementing them), where optimal solutions at a
+ # higher level are combined into lower level solutions or optima of optimal solutions
+ # at higher level are calculated:
+ # * Level 1: Finding an optimal quadrature tuple (by finding optimum of level 2 optima)
+ # * Level 2: Split by parallelizability and combine optima into optimal solution
+ # * Level 3: Optimize number of different inputs to consider
+ # * Level 4: Optimize horizontal/vertical/hybrid strategy
+ width = get_vcl_type_size(dtype_floatingpoint())
+ qp, sfdict = level1_optimal_vectorization_strategy(active_sumfacts, width)
+
+
+# TODO: Check how the 'fromlist' generator fits into the new overall picture
+#
+# if get_form_option("vectorization_strategy") == "fromlist":
+# # This is a bit special and does not follow the minimization procedure at all
+#
+# def _choose_strategy_from_list(stage1_sumfacts):
+# strategy = 0
+# for qp in quad_points:
+# for strat in fixed_quad_vectorization_opportunity_generator(frozenset(stage1_sumfacts), width, qp):
+# if strategy == int(get_form_option("vectorization_list_index")):
+# # Output the strategy and its cost into a separate file
+# if get_global_context_value("form_type") == "jacobian_apply":
+# with open("strategycosts.csv", "a") as f:
+# f.write("{} {}\n".format(strategy, strategy_cost((qp, strat))))
+# return qp, strat
+# strategy = strategy + 1
+#
+# raise PerftoolVectorizationError("Specified vectorization list index '{}' was too high!".format(get_form_option("vectorization_list_index")))
+#
+# s1_sumfacts = frozenset(sf for sf in active_sumfacts if sf.stage == 1)
+#
+# total = sum(len([s for s in fixed_quad_vectorization_opportunity_generator(frozenset(s1_sumfacts), width, qp)]) for qp in quad_points)
+# print("'fromlist' vectorization is attempting to pick #{} of {} strategies...".format(int(get_form_option("vectorization_list_index")),
+# total))
+# qp, sfdict = _choose_strategy_from_list(s1_sumfacts)
+#
+# keys = frozenset(sf.input_key for sf in active_sumfacts if sf.stage != 1)
+# for key in keys:
+# key_sumfacts = frozenset(sf for sf in active_sumfacts if sf.input_key == key)
+# minimum = min(fixed_quad_vectorization_opportunity_generator(key_sumfacts, width, qp),
+# key=fixedqp_strategy_costfunction(qp))
+# sfdict = add_to_frozendict(sfdict, minimum)
set_quadrature_points(qp)
@@ -239,13 +235,28 @@ def decide_vectorization_strategy():
_cache_vectorization_info(sf, sfdict[sf])
-def fixed_quadrature_optimal_vectorization(sumfacts, width, qp):
- """ For a given quadrature point tuple, find the optimal strategy!
+def level1_optimal_vectorization_strategy(sumfacts, width):
+ # Gather a list of possible quadrature point tuples
+ quad_points = [quadrature_points_per_direction()]
+ if get_form_option("vectorization_allow_quadrature_changes"):
+ sf = next(iter(sumfacts))
+ depth = 1
+ while depth <= width:
+ i = 0 if sf.matrix_sequence[0].face is None else 1
+ quad = list(quadrature_points_per_direction())
+ quad[i] = round_to_multiple(quad[i], depth)
+ quad_points.append(tuple(quad))
+ depth = depth * 2
+ quad_points = list(set(quad_points))
- In order to have this scale sufficiently, we cannot simply list all vectorization
- opportunities and score them individually, but we need to do a divide and conquer
- approach.
- """
+ # Find the minimum cost strategy between all the quadrature point tuples
+ optimal_strategies = {qp: level2_optimal_vectorization_strategy(sumfacts, width, qp) for qp in quad_points}
+ qp = min(optimal_strategies, key=lambda qp: strategy_cost((qp, optimal_strategies[qp])))
+
+ return qp, optimal_strategies[qp]
+
+
+def level2_optimal_vectorization_strategy(sumfacts, width, qp):
# Find the sets of simultaneously realizable kernels (thats an equivalence relation)
keys = frozenset(sf.input_key for sf in sumfacts)
--
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