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## @package memonger
# Module caffe2.python.memonger
import networkx as nx
import collections
import time
import copy
from caffe2.python import workspace, core
from caffe2.proto import caffe2_pb2
import enum
import logging
from future.utils import viewitems, viewvalues
import caffe2.python._import_c_extension as C
log = logging.getLogger("memonger")
log.setLevel(logging.INFO)
LiveRange = collections.namedtuple('LiveRange', ["defined", "used", "size"])
def share_grad_blobs(
net,
losses,
param_grads,
namescope,
dont_share_blobs=None,
share_activations=False,
blob_shapes=None,
):
'''
Implements similar optimization as Torch's shareGradInput():
for the gradients that are passed between layers, share blobs between
operators when possible. This yields significant memory savings with
deep networks.
Returns an optimized protobuf (assign to net._net)
'''
def is_grad_blob(b):
name = str(b)
# Note: need to look at _{namescope} pattern as it matches
# to handle the auto-split gradients
return name.endswith("_grad") and (name.startswith(namescope) or
name.startswith("_" + namescope)) and name not in param_grads
def is_grad_op(op):
# TODO: something smarter
for b in list(op.input) + list(op.output):
if is_grad_blob(b):
return True
return False
log.warn("NOTE: Executing memonger to optimize gradient memory")
# Collect ops that have something to do with gradients
if namescope != "" and not namescope.endswith("/"):
namescope += "/"
netproto = copy.deepcopy(net.Proto())
activations = []
external_output = set(net.Proto().external_output)
# Hacky way to get activations, think of a better way
for op in net.Proto().op:
for b in op.output:
if b + "_w" in op.input and b not in external_output:
activations.append(b)
# Remove last activations, as they are usually accessed externally
activations = set(activations[:-2])
# Gradient ops
grad_op_indices = []
for idx, op in enumerate(netproto.op):
if (is_grad_op(op)):
grad_op_indices.append(idx)
shared_blobs = set()
for op in net.Proto().op:
for b in list(op.input) + list(op.output):
if is_grad_blob(b) or (share_activations and b in activations):
shared_blobs.add(b)
start_time = time.time()
optim_str = C.memonger_compute_blob_recycling_for_dag(
netproto.SerializeToString(),
[str(s).encode('utf-8') for s in losses],
grad_op_indices,
set(str(s).encode('utf-8') for s in shared_blobs),
namescope.encode('utf-8'),
set() if dont_share_blobs is None else dont_share_blobs,
{} if blob_shapes is None else blob_shapes
)
log.info("Memonger memory optimization took {} secs".format(
time.time() - start_time),
)
optim = caffe2_pb2.NetDef()
optim.ParseFromString(optim_str)
assert verify_graph_equality(net.Proto(), optim), \
"Memonger graph is not equal to original."
assert verify_inplace_blobs(net.Proto(), optim), \
"Inplace assignments differ in memonger net."
return optim
def optimize_inference_for_dag(net, input_blobs, namescope=""):
netproto = copy.deepcopy(net.Proto())
external_input = set(net.Proto().external_input)
external_output = set(net.Proto().external_output)
def is_activation_blob(b):
return b not in external_input and b not in external_output
activation_blobs = set()
seen_as_output = set()
ops = list(net.Proto().op)
op_indices = [index for index, op in enumerate(net.Proto().op)]
# Sanity check: check that all external inputs are properly accounted
# and that no gradient ops are included in 'net'
for op in ops:
for b in op.input:
if is_activation_blob(b):
activation_blobs.add(b)
if b not in seen_as_output:
raise AssertionError("{} not in external input".format(b))
for b in op.output:
if is_activation_blob(b):
activation_blobs.add(b)
seen_as_output = seen_as_output.union(set(op.output))
assert not op.is_gradient_op, \
"You can only pass inference-only nets to optimize_inference_for_dag"
start_time = time.time()
optim_str = C.memonger_compute_blob_recycling_for_dag(
netproto.SerializeToString(),
[str(s).encode('utf-8') for s in input_blobs],
op_indices,
set(str(s).encode('utf-8') for s in activation_blobs),
namescope.encode('utf-8'),
set(),
{}
)
log.info("Memonger memory optimization took {} secs".format(
time.time() - start_time),
)
optim = caffe2_pb2.NetDef()
optim.ParseFromString(optim_str)
assert verify_graph_equality(net.Proto(), optim), \
"Memonger graph is not equal to original."
assert verify_inplace_blobs(net.Proto(), optim), \
"Inplace assignments differ in memonger net."
return optim
def estimate_memory_usage(protos, shapes, types, devicescope):
import numpy as np
'''
Estimate memory usage of a model. This is an estimate because
we assume a single threaded execution and miss some internal
memory usage of operators. Only estimates the memory for a given
device scope.
Also, currently it does not handle correctly if blob sizes vary
during execution, as it uses only the final blob size.
Returns (total, highwater, by op type) memory allocation in bytes.
'''
sizeofs = {
caffe2_pb2.TensorProto.DOUBLE: 8,
caffe2_pb2.TensorProto.FLOAT: 4,
caffe2_pb2.TensorProto.FLOAT16: 2,
caffe2_pb2.TensorProto.INT32: 4,
caffe2_pb2.TensorProto.INT8: 1,
caffe2_pb2.TensorProto.UINT8: 1,
caffe2_pb2.TensorProto.UINT16: 2,
caffe2_pb2.TensorProto.INT16: 2,
caffe2_pb2.TensorProto.BOOL: 1,
caffe2_pb2.TensorProto.INT64: 8,
}
def split_net(proto):
ops = [op for op in proto.op if
op.device_option == devicescope or op.type in {"Free", "Alias"}]
del proto.op[:]
proto.op.extend(ops)
return proto
def num_bytes(blob):
if blob not in shapes or blob not in types:
log.warning("Unknown blob encountered: {}".format(blob))
return 0
sizeof = sizeofs[types[blob]]
return sizeof * np.prod(shapes[blob])
protos = [split_net(proto) for proto in protos]
allocs_by_ops = collections.defaultdict(lambda: 0)
# Evaluate
current_allocated = 0
max_allocated = 0
total_allocated = 0
allocated = set()
for proto in protos:
for op in proto.op:
if op.type == "Free" or op.type == "Alias":
for o in op.output:
if o in allocated:
current_allocated -= num_bytes(o)
allocated.remove(o)
else:
for output in op.output:
if output not in allocated:
nbytes = num_bytes(output)
total_allocated += nbytes
current_allocated += nbytes
max_allocated = max(max_allocated, current_allocated)
allocated.add(output)
allocs_by_ops[op.type] += nbytes
return (total_allocated, max_allocated, allocs_by_ops)
def release_blobs_when_used(netproto, dont_free_blobs, selector_fun=None):
'''
Insert Free-ops after a blob has been used the last time, so that its
memory can be reclaimed. Use this only with efficient caching memory
managers (such as CUB, --caffe2_cuda_memory_pool=cub).
Blobs used with Alias op won't be freed.
@dont_free_blobs: is a set of blobs that should not be freed
@selector_fun: optional lambda that return True if blob name
can be released. Use for easy special filtering, like
excluding blobs with "loss" in the name.
Returns a new protobuffer. To use with a model, use:
model.net._net = memonger.release_blobs_when_used(..)
'''
input_blobs = set()
can_release = set()
alias_blobs = set()
netproto = copy.deepcopy(netproto)
for op in netproto.op:
if op.type == 'Alias':
alias_blobs.add(op.input[0])
continue
for inp in op.input:
input_blobs.add(inp)
for outp in op.output:
if outp not in input_blobs:
if selector_fun is None or selector_fun(outp):
can_release.add(outp)
# Remove such blobs that are not input at all and external outputs
can_release = can_release - set(netproto.external_output)
can_release = can_release.intersection(input_blobs)
can_release = can_release - dont_free_blobs
can_release = can_release - alias_blobs
ops = list(netproto.op)
# .. then find last use of each can-release blob, and insert a Free op
for j in reversed(range(0, len(netproto.op))):
op = netproto.op[j]
for inp in op.input:
if inp in can_release:
can_release.remove(inp)
ops.insert(j + 1, core.CreateOperator("Free", [inp], [inp]))
del netproto.op[:]
netproto.op.extend(ops)
return netproto
def _find_source_nodes(g):
''' Return nodes without predecessors '''
ret = []
for cn in g:
cur_pred = list(g.predecessors(cn))
if not cur_pred:
ret.append(cn)
return ret
def _find_target_nodes(g):
''' Return nodes without successors '''
ret = []
for cn in g:
cur_succ = list(g.successors(cn))
if not cur_succ:
ret.append(cn)
return ret
def _add_single_target_ifneeded(g):
targets = _find_target_nodes(g)
assert len(targets) >= 1
if len(targets) == 1:
return g
ret = copy.deepcopy(g)
def _next_available_idx(g):
ret = -1
for cn in g:
if cn > ret:
ret = cn
ret += 1
return ret
target_node_idx = _next_available_idx(g)
ret.add_node(target_node_idx)
for cn in targets:
ret.add_edge(cn, target_node_idx)
return ret
def _get_path(pred_list, dist_list):
''' Get the path from nx.bellman_ford()'s output '''
# distances are negative
assert all(dist_list[x] <= 0 for x in dist_list)
# node with longest distance to source is the target
target = min(dist_list, key=lambda x: dist_list[x])
ret = []
cur = target
while cur is not None:
ret.append(cur)
# Hack to get networkx 2.0 happy: it uses list in pred.
# TODO(tulloch): are there cases with multiple predecessors?
try:
cur = pred_list[cur][0] if pred_list[cur] else None
except TypeError:
cur = pred_list[cur]
return list(reversed(ret))
def _get_longest_paths(g, source_nodes):
''' Get the longest path for nodes in 'source_nodes'
Find with bellman_ford() by setting weight = -1
'''
ng = copy.deepcopy(g)
for u, v in ng.edges():
ng[u][v]["weight"] = -1
ret = {}
for cn in source_nodes:
pred, dist = nx.bellman_ford_predecessor_and_distance(ng, cn, weight="weight")
path = _get_path(pred, dist)
assert path[0] == cn
assert len(path) - 1 == -dist[path[-1]]
ret[cn] = path
return ret
def _build_tree(paths):
''' Build a tree for given paths based on common elements.
Last elements of all paths are the same, which is the root of the tree.
'''
assert all(cp[-1] == paths[0][-1] for cp in paths)
g = nx.DiGraph()
node_set = {y for x in paths for y in x}
g.add_nodes_from(node_set)
for cp in paths:
for ce in zip(cp[0:-1], cp[1:]):
g.add_edge(ce[1], ce[0])
root = paths[0][-1]
_compute_tree_height(g, root)
return (g, root)
def _compute_tree_height(g, root):
''' Compute the heights of the tree for all nodes
Height of leaves are 0
'''
def _get_height(root):
children = list(g.successors(root))
height = 0
if children:
child_heights = [_get_height(x) for x in children]
height = max(child_heights) + 1
g.nodes[root]["height"] = height
return height
_get_height(root)
def _sort_tree_leaves(g, root):
''' For each node, sort its child nodes based on the height of the nodes.
Return the leaf nodes of the tree after sorting.
'''
def _get_height(root):
return g.nodes[root]["height"]
def _get_sorted_leaves(root):
children = list(g.successors(root))
if not children:
return [root]
child_heights = [_get_height(x) for x in children]
order = sorted(range(len(children)), key=lambda x: child_heights[x])
ret = []
for co in order:
cr = children[co]
ret += _get_sorted_leaves(cr)
return ret
return _get_sorted_leaves(root)
def topological_sort_traversal_longest_path(g):
''' The graph 'g' may contain several source nodes (nodes without incoming
edge), which could be in any order and still be a valid
topological sorting result. We would like to arrange these source nodes
so that the average live spans of the computed blobs are shorter.
The idea is to sort the source nodes based on the length of their path to
the target node so that the one with longer path is used first.
This is done by:
- Add a single target node if there are multiple target nodes in 'g'.
- Find the longest path between each source and the target node.
- Convert the longest paths to a tree with the target node being the root
and source nodes being the leaves.
- Sort the nodes of the tree based on the height of the tree.
'''
gt = _add_single_target_ifneeded(g)
source_nodes = _find_source_nodes(gt)
lpaths = _get_longest_paths(gt, source_nodes)
tree, root = _build_tree(list(viewvalues(lpaths)))
sorted_sources = _sort_tree_leaves(tree, root)
assert(sorted(sorted_sources) == sorted(source_nodes))
if nx.__version__ < '2.0':
ret = nx.topological_sort(g, sorted_sources)
else:
# Manually making a sorted descendent list
dependency_order = list(sorted_sources)
seen_nodes = set(sorted_sources)
for s in sorted_sources:
desc = nx.descendants(g, s)
for d in desc:
if d not in seen_nodes:
seen_nodes.add(d)
dependency_order.append(d)
sort_key = dict((v, len(dependency_order) - i) for i, v in enumerate(dependency_order))
ret = nx.algorithms.dag.lexicographical_topological_sort(
g, key=lambda x: sort_key[x])
ret = list(ret)
assert(len(ret) == len(g.nodes))
return ret
def topological_sort_traversal(g):
return list(nx.topological_sort(g))
def compute_ranges(linearized_ops, blob_sizes=None):
if not blob_sizes:
log.warning('Provide blob sizes to get more accurate assignments.')
blobs = collections.defaultdict(
lambda: LiveRange(defined=None, used=None, size=None))
for i, op in enumerate(linearized_ops):
for blob in op.input:
used = blobs[blob].used
if used is None:
used = i
else:
used = max(used, i)
blobs[blob] = blobs[blob]._replace(used=used)
blob_size = blob_sizes[blob] if blob_sizes else None
assert not blob_sizes or blob_size is not None
blobs[blob] = blobs[blob]._replace(size=blob_size)
for blob in op.output:
defined = blobs[blob].defined
if defined is None:
defined = i
else:
defined = min(defined, i)
blobs[blob] = blobs[blob]._replace(defined=defined)
blob_size = blob_sizes[blob] if blob_sizes else None
assert not blob_sizes or blob_size is not None
blobs[blob] = blobs[blob]._replace(size=blob_size)
return blobs
def is_compatible(candidate_range, assignment, static_blobs):
(name, range_) = assignment[-1]
if name in static_blobs:
return False
if candidate_range.defined is None or range_.defined is None \
or range_.used is None:
return False
return candidate_range.defined > range_.used
def compute_blob_assignments(assignments):
blob_assignments = {}
for assignment in assignments:
if len(assignment) == 1:
continue
last_blob, _ = assignment[-1]
for (blob, _) in assignment:
blob_assignments[blob] = last_blob
return blob_assignments
def _get_max_size(assignment):
if not assignment:
return 0
ret = max([x[1].size for x in assignment])
ret = 0 if ret is None else ret
return ret
def get_memory_usage(assignments):
ret = 0
for cur in assignments:
ret += _get_max_size(cur)
return ret
def compute_assignments_greedy(ranges_sorted, init_assignments=None):
assignments = init_assignments or []
visited = {y[0] for x in assignments for y in x}
for (name, range_) in ranges_sorted:
if name in visited:
continue
assigned = False
best_assignment = 0
min_dist = float("inf")
candidate_size = range_.size or 0
for idx, assignment in enumerate(assignments):
if is_compatible(range_, assignment, []):
assigned = True
dist = abs(_get_max_size(assignment) - candidate_size)
if dist < min_dist:
min_dist = dist
best_assignment = idx
if assigned:
assignment = assignments[best_assignment]
assignment.append((name, range_))
else:
assignments.append([(name, range_)])
return assignments
def _get_count(assignments):
''' Return number of blobs in assignments '''
if assignments:
return sum([len(x) for x in assignments])
return 0
def compute_assignments_dp(ranges_sorted, init_assignment, counter=None):
''' Compute assignment for blobs in 'ranges_sorted' on top of 'init_assignment'
using dynamic programming + recursion.
ranges_sorted: blobs sorted by 'used'
init_assignment: assignment to start with, blobs in 'ranges_sorted' should
not be used in 'init_assignment'
Using f(b, k, init) to represent the best assignment for blobs b[0:k]
given initial assignment 'init', we have
f(b, k, init) = f(b, j, init) +
find_best(b[j:k], f(b, j, init))
where j is the index of the last best assignment that is independent of
blob b[k - 1] (b[k - 1] is compatible with all assignments in
f(b, j, init)), and find_best(b1, init1) gives the best assignment
for blobs in 'b1' based on the initial assignment 'init1', and blobs
b1[0:-1] should be incompatible with b1[-1]. f(b, len(b), []) gives
the best assignment for blobs 'b'.
For find_best(b, init), since b[0:-1] are not compatible with b[-1], we
could reduce it to a smaller problem to find best assignment for b[0:-1]
as
find_best(b, init) = min {
f(b[0:-1], len(b) - 1, init - x) + [x, b[-1]] for x in init, or
f(b[0:-1], len(b) - 1, init) + [b[-1]]
}
where min{} gives the assignment with minimum memory usage.
'''
def _get_compatible_prev(candidate_range, best_assignments, cur_idx):
''' Find closest position k of best_assignments that is independent of
candidate_range that candiate_range is compatible with all assignments
in best_assignments[k].
Return -1 if not found.
'''
def is_compatible_all(candidate_range, assignments):
''' return true if compatible for all assignments in assignments '''
return all([is_compatible(candidate_range[1], x, []) for x in assignments])
ii = cur_idx - 1
while ii >= 0:
cba = best_assignments[ii]
if is_compatible_all(candidate_range, cba):
return ii
ii -= 1
return -1
def _find_best(ranges, init_assignment, prev_best_assignment, counter):
''' Find the best assignment for blobs 'ranges' given an initialized
assignment 'init_assignment'.
Blobs in ranges[0:-1] should be incompatible with blob range[-1].
'prev_best_assignment': best assignment for blobs in ranges[:-1]
By assigning ranges[-1] to each assignment k in 'init_assignment' or
in a new assignment, the problem becomes a smaller problem to find
the best assignment for ranges[0:-1] given the initial assignment
init_assigment[0:k, (k+1):-1].
'''
# Blob to check
find_range = ranges[-1]
# Blobs in ranges[0:-1] are incompatible with ranges[-1] so that we can
# reduce it to a smaller problem.
assert all(not is_compatible(x[1], [find_range], []) for x in ranges[0:-1])
sz = len(init_assignment)
best_candidates = []
# Try to assign 'find_range' to each assignment in init_assignment
for ii in range(sz):
if not is_compatible(find_range[1], init_assignment[ii], []):
continue
cur_best = copy.deepcopy(init_assignment)
cur_best[ii].append(find_range)
if len(ranges) > 1:
cur_best_tmp = [x for i, x in enumerate(cur_best) if i != ii]
# reduce to a smaller dp problem
cur_best_tmp = compute_assignments_dp(
ranges[:-1], cur_best_tmp, counter)
cur_best = cur_best_tmp + [cur_best[ii]]
best_candidates.append(cur_best)
# Try to put 'find_range' in a new assignment
best_candidates.append(prev_best_assignment + [[find_range]])
ret = min(best_candidates, key=lambda x: get_memory_usage(x))
return ret
if not counter:
counter = [0]
counter[0] += 1
if counter and counter[0] % 5000 == 0:
rs = [ranges_sorted[0][1].defined, ranges_sorted[-1][1].used]
log.info('Finding assignments {} ({} -> {})...'.format(
counter[0], rs[0], rs[1]))
init_assignment = init_assignment or []
# best_assignments[k]: best assignments for first k blobs ranges_sorted[0:(k+1)]
best_assignments = []
# Find best assignment for blobs ranges_sorted[0:ii]
for ii, cur_range in enumerate(ranges_sorted):
# closest best_assignment that is independent of ranges_sorted[ii]
prev_idx = _get_compatible_prev(cur_range, best_assignments, ii)
prev_best = copy.deepcopy(init_assignment) if prev_idx < 0 else \
copy.deepcopy(best_assignments[prev_idx])
# Need to find best assignment for blobs in 'ranges_part'
ranges_part = ranges_sorted[(prev_idx + 1):(ii + 1)]
cur_best = _find_best(
ranges_part, prev_best,
best_assignments[-1] if best_assignments else init_assignment,
counter)
assert _get_count(cur_best) == _get_count(prev_best) + len(ranges_part)
best_assignments.append(copy.deepcopy(cur_best))
assert len(best_assignments) == len(ranges_sorted)
best = best_assignments[-1]
return best
def get_updated_ranges(ranges, max_live=None):
''' Set LiveRange.defined = -1 if it is None
Set LiveRange.used = max_live if it is None
Set LiveRanee.size = 1 if it is None
'''
def _get_max_live(ranges):
max_live = max(x[1].used for x in ranges if x[1].used) + 1
return max_live
def _update_range(x, max_live, size):
cx = x
if x[1].defined is None:
cx = (cx[0], cx[1]._replace(defined=-1))
if x[1].used is None:
cx = (cx[0], cx[1]._replace(used=max_live))
if x[1].size is None:
cx = (cx[0], cx[1]._replace(size=size))
return cx
if max_live is None:
max_live = _get_max_live(ranges)
ranges = [_update_range(x, max_live, 1) for x in ranges]
return ranges
def compute_assignments(ranges, static_blobs, algo):
'''
algo: Method used to find assignments (AssignmentAlgorithm.GREEDY or
AssignmentAlgorithm.DYNAMIC_PROGRAMMING).
AssignmentAlgorithm.DYNAMIC_PROGRAMMING gives optimal solution at the
cost of more computation.
AssignmentAlgorithm.GREEDY may be better in the case 'blob_sizes' is
not provided.
'''
# Sort the ranges based on when they are last used.
# If LiveRange.used is None, then the blob is never used and could
# be consumed externally. Sort these to the end of the list as opposed
# to the beginning so that they can be shared as well.
ranges = sorted(
viewitems(ranges),
key=lambda p: (p[1].used is None, p[1].used),
)
# Update None values
ranges = get_updated_ranges(ranges)
# Sharable blobs
ranges_sharable = [x for x in ranges if x[0] not in static_blobs]
# Static blobs, not sharable
ranges_static = [x for x in ranges if x[0] in static_blobs]
log.info("Total sharable blobs {}".format(len(ranges_sharable)))
best_assignment = []
if algo == AssignmentAlgorithm.DYNAMIC_PROGRAMMING:
best_assignment = compute_assignments_dp(ranges_sharable, [])
elif algo == AssignmentAlgorithm.GREEDY:
best_assignment = compute_assignments_greedy(ranges_sharable, [])
else:
assert "Invalid algo name {}".format(algo)
best_assignment += [[x] for x in ranges_static]
# verify_assignments(best_assignment)
return best_assignment
def verify_assignments(assignments):
for cur in assignments:
for x, y in zip(cur[0:-1], cur[1:]):
assert x[1].used < y[1].defined
def compute_interference_graph(ops):
g = nx.DiGraph()
for i, op in enumerate(ops):
g.add_node(i, op=op)
for i, parent_op in enumerate(ops):
for j, child_op in enumerate(ops):
if i >= j:
continue
if any(output in child_op.input for output in parent_op.output):
deps = set(child_op.input).intersection(parent_op.output)
g.add_edge(i, j, deps=deps)
assert nx.is_directed_acyclic_graph(g), child_op
return g
Optimization = collections.namedtuple(
'Optimization', ['net', 'assignments', 'blob_assignments'])
def apply_assignments(net, blob_assignments):
def canonical_name(blob):
if blob not in blob_assignments:
return blob
return blob_assignments[blob]
for op in net.op:
# Descend into subnets of the recurrent network
if op.type.startswith('RecurrentNetwork'):
apply_recurrent_blob_assignments(op, blob_assignments, canonical_name)
for i, input_ in enumerate(op.input):
op.input[i] = canonical_name(input_)
for i, output in enumerate(op.output):
op.output[i] = canonical_name(output)
def apply_recurrent_blob_assignments(op, blob_assignments, canonical_name):
log.debug("Applying assignments to recurrent op: {}".format(op.type))
# Apply on alias_dst
alias_dst_args = [a for a in op.arg if a.name.endswith("alias_dst")]
for alias_dst in alias_dst_args:
for i, blob in enumerate(alias_dst.strings):
alias_dst.strings[i] = canonical_name(blob.decode()).encode()
# Apply on link_external
link_external_args = [a for a in op.arg if a.name.endswith("link_external")]
for link_external in link_external_args:
for i, blob in enumerate(link_external.strings):
link_external.strings[i] = canonical_name(blob.decode()).encode()
# Recurse into step nets
step_args = [a for a in op.arg if a.name.endswith("step_net")]
for step_arg in step_args:
apply_assignments(step_arg.n, blob_assignments)
for i, einp in enumerate(step_arg.n.external_input):
if einp in blob_assignments:
step_arg.n.external_input[i] = canonical_name(einp)
# Store renamings
for blob, renamed in viewitems(blob_assignments):
if blob in list(op.input) + list(op.output):
a = caffe2_pb2.Argument()
a.name = blob + ".rename"
a.s = str(renamed).encode("ascii")
op.arg.extend([a])
class AssignmentAlgorithm(enum.Enum):
GREEDY = 0
DYNAMIC_PROGRAMMING = 1
def optimize_inference_fast(net, static_blobs):
optim = caffe2_pb2.NetDef()
optim_str = C.memonger_optimize_inference_net(
net.SerializeToString(),
[str(s).encode('utf-8') for s in static_blobs]
)
optim.ParseFromString(optim_str)
return optim
def optimize_interference(net, static_blobs,
ordering_function=topological_sort_traversal,
blob_sizes=None,
algo=AssignmentAlgorithm.GREEDY):
"""
ordering_function: topological_sort_traversal or
topological_sort_traversal_longest_path.
topological_sort_traversal_longest_path gives better
results but needs a bit more computation.
algo: Method used to find assignments (AssignmentAlgorithm.GREEDY or
AssignmentAlgorithm.DYNAMIC_PROGRAMMING).
AssignmentAlgorithm.DYNAMIC_PROGRAMMING gives optimal solution at the
cost of more computation.
AssignmentAlgorithm.GREEDY may be better in the case 'blob_sizes' is
not provided.
"""
"""
1) Use a BFS traversal of the execution graph to generate an
ordering of the node executions.
2) Generate use-def ranges for each `blob` in the BFS traversal
order.
3) Assign blobs to `canonical blobs`
4) Rename blobs to canonical blobs
"""
net = copy.deepcopy(net)
g = compute_interference_graph(net.op)
ordering = ordering_function(g)
linearized_ops = [net.op[i] for i in ordering]
# Reorder ops in net based on the computed linearlized order.
# If the graph has multiple topological orderings and if the NetDef's
# ordering differs from the order used to compute ranges, then the
# runtime might end up overwriting blobs before they are used.
del net.op[:]
net.op.extend(linearized_ops)
ranges = compute_ranges(linearized_ops, blob_sizes)
assignments = compute_assignments(ranges, static_blobs, algo)
blob_assignments = compute_blob_assignments(assignments)
apply_assignments(net, blob_assignments)
return Optimization(
net=net,
blob_assignments=blob_assignments,
assignments=assignments)
def verify_inplace_blobs(net_a, net_b):
"""
Verifies that net_a and net_b have the same in-place blob assignments.
Particularly, that memonger did not add an in-place assignment when that
did not exist before.
"""
def get_inplaces(op):
out = list(op.output)
inplaces = []
for j, inp in enumerate(op.input):
if inp in out:
inplaces.append([j, out.index(inp)])
return inplaces
for op_a, op_b in zip(net_a.op, net_b.op):
if op_a.type != op_b.type:
return False
if get_inplaces(op_a) != get_inplaces(op_b):
return False
return True
def verify_graph_equality(net_a, net_b):
"""
Determines if the execution of two graphs are identical.
That is, all inputs blobs are mapped to the same output blobs
for each operator in their respective positions.
This is meant to check the output of memonger with the original graph.
It assumes that the nets have same external input and output.
O(E) runtime + O(1) amortized cost to hash for python dict
"""
def parent_list(ops):
parent_list = [[] for _ in ops]
edge_owner = {}
for i, op in enumerate(ops):
for blob in op.input:
parent_id = edge_owner.get(blob)
if parent_id is not None:
parent_list[i].append(parent_id)
for blob in op.output:
edge_owner[blob] = i
return parent_list
# Operator wise equality checks
if (len(net_a.op) != len(net_b.op)):
return False
for op_a, op_b in zip(net_a.op, net_b.op):
if (op_a.type != op_b.type or
op_a.device_option != op_b.device_option or
op_a.engine != op_b.engine):
return False
# Print debug info
parent_list_a = parent_list(net_a.op)
parent_list_b = parent_list(net_b.op)
if parent_list_a != parent_list_b:
j = 0
for a, b in zip(parent_list_a, parent_list_b):
if a != b:
print("Difference {} vs {} \n {}".format(
j, net_a.op[j], net_b.op[j]))
print("Parents: {} vs {}".format(a, b))
j += 1
# Net wise equality check
return parent_list_a == parent_list_b
Statistics = collections.namedtuple(
'Statistics', ['baseline_nbytes', 'optimized_nbytes'])
def blob_nbytes(blob):
sz = 0
try:
sz = workspace.FetchBlob(blob).nbytes
except Exception:
log.warning('Error when fetching blob {}'.format(blob))
return sz
def compute_statistics(assignments):
blob_bytes = {
blob: blob_nbytes(blob) for assignment in assignments
for (blob, _) in assignment}
baseline_nbytes = sum(viewvalues(blob_bytes))
optimized_nbytes = sum(
max(blob_bytes[blob] for (blob, _) in assignment)
for assignment in assignments)
return Statistics(
baseline_nbytes=baseline_nbytes,
optimized_nbytes=optimized_nbytes)
def collect_blob_sizes(net):
blobs = {}
for op in net.op:
for blob in op.input:
blobs[blob] = blob_nbytes(blob)
for blob in op.output:
blobs[blob] = blob_nbytes(blob)
return blobs
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