# Copyright (c) 2021 PaddlePaddle Authors. All Rights Reserved. # # Licensed under the Apache License, Version 2.0 (the "License"); # you may not use this file except in compliance with the License. # You may obtain a copy of the License at # # http://www.apache.org/licenses/LICENSE-2.0 # # Unless required by applicable law or agreed to in writing, software # distributed under the License is distributed on an "AS IS" BASIS, # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. # See the License for the specific language governing permissions and # limitations under the License. from paddle.framework import core from paddle.fluid import unique_name from .pass_base import PassBase, PassType, register_pass import numpy as np def find_adjacent_match_sequences(iterable, filter_func, adjacent_filter_func=None): n = len(iterable) match_sequences = [] if adjacent_filter_func is None: adjacent_filter_func = lambda ref_op, new_op: True i = 0 while True: while i < n and not filter_func(iterable[i]): i += 1 j = i + 1 while j < n and filter_func(iterable[j]) and adjacent_filter_func( iterable[i], iterable[j]): j += 1 if i < n and j <= n: match_sequences.append((i, j)) i = j + 1 if i >= n: break return match_sequences def insert_fuse_all_reduce_ops(block, reversed_op_indices, input_var_names, output_var_names, dtype, attrs): fused_var = block.create_var(name=unique_name.generate( "FusedOutput_{}".format(input_var_names[0])), dtype=dtype) # FIXME(zengjinle): here we assume that we use # c_sync_calc_stream/c_sync_comm_stream to do sync. # But someone may use c_wait_compute/c_wait_comm instead. if not attrs["use_calc_stream"]: ring_id = attrs["ring_id"] new_op_indices = list(reversed_op_indices) for i, op_idx in enumerate(reversed_op_indices): prev_op_idx = op_idx - 1 while prev_op_idx >= 0 and block.ops[ prev_op_idx].type == "c_sync_calc_stream": new_op_indices.append(prev_op_idx) prev_op_idx -= 1 if i > 0: next_op_idx = op_idx + 1 n = len(block.ops) while next_op_idx < n and block.ops[ next_op_idx].type == "c_sync_comm_stream": assert block.ops[next_op_idx].attr("ring_id") == ring_id new_op_indices.append(next_op_idx) new_op_indices = list(set(new_op_indices)) new_op_indices.sort(reverse=True) reversed_op_indices = new_op_indices insert_idx = reversed_op_indices[0] + 1 op_role_key = core.op_proto_and_checker_maker.kOpRoleAttrName() concated_shapes = [] concated_ranks = [] for var_name in output_var_names: shape = block._find_var_recursive(var_name).shape concated_shapes.extend(shape) concated_ranks.append(len(shape)) coalesce_tensor_op_kwargs = { "type": "coalesce_tensor", "inputs": { "Input": input_var_names, }, "outputs": { "Output": output_var_names, "FusedOutput": fused_var, }, "attrs": { "use_align": True, "dtype": dtype, "concated_shapes": concated_shapes, "concated_ranks": concated_ranks, op_role_key: attrs[op_role_key], }, } if not attrs["use_calc_stream"]: block._insert_op_without_sync(insert_idx, type="c_sync_calc_stream", inputs={"X": fused_var}, outputs={ "Out": fused_var, op_role_key: attrs[op_role_key] }) insert_idx += 1 # c_allreduce_sum should insert block._insert_op_without_sync(insert_idx, type="c_allreduce_sum", inputs={"X": fused_var}, outputs={"Out": fused_var}, attrs=attrs) for op_idx in reversed_op_indices: block._remove_op(op_idx) return coalesce_tensor_op_kwargs def has_same_attrs(op1, op2, attr_names): for attr_name in attr_names: if op1.attr(attr_name) != op2.attr(attr_name): return False return True def filter_all_collective_op_indices(block): # NOTE: should add more collective ops all_collective_ops = { "c_allreduce_sum", "c_allreduce_prod", "c_allreduce_max", "c_allreduce_min", "c_allgather", "c_broadcast", } match_op_indices = [] for i, op in enumerate(block.ops): if op.type in all_collective_ops: match_op_indices.append(i) return match_op_indices def find_all_fuse_all_reduce_groups(block): collective_op_indices = filter_all_collective_op_indices(block) collective_ops = [block.ops[i] for i in collective_op_indices] def is_valid_allreduce_op(op): if op.type != "c_allreduce_sum" or op.attr("use_model_parallel"): return False in_var_name = op.input("X")[0] out_var_name = op.output("Out")[0] if in_var_name != out_var_name: return False in_var = block._find_var_recursive(in_var_name) assert in_var is not None if in_var.type != core.VarDesc.VarType.LOD_TENSOR: return False shape = in_var.shape if any([s <= 0 for s in shape]): return False return True same_attr_names = [ "ring_id", "use_calc_stream", core.op_proto_and_checker_maker.kOpRoleAttrName(), core.op_proto_and_checker_maker.kOpDeviceAttrName(), ] def is_same_adjacent_op(ref_op, new_op): if not has_same_attrs(ref_op, new_op, same_attr_names): return False ref_op_in_var = block._find_var_recursive(ref_op.input("X")[0]) new_op_in_var = block._find_var_recursive(new_op.input("X")[0]) if ref_op_in_var.dtype != new_op_in_var.dtype: return False return True match_seqs = find_adjacent_match_sequences(collective_ops, is_valid_allreduce_op, is_same_adjacent_op) new_match_seqs = [] for i, j in match_seqs: new_match_seqs.append([collective_op_indices[k] for k in range(i, j)]) return new_match_seqs def split_fuse_all_reduce_groups_by_deps(block, groups, op_deps): new_groups = [] def insert_new_group(op_indices, start_idx, end_idx): if end_idx - start_idx > 1: new_groups.append(op_indices[start_idx:end_idx]) for op_indices in groups: n = len(op_indices) assert n > 0 if n == 1: continue start_idx = 0 k = start_idx + 1 while k < n: found_group = False for prev_idx in range(start_idx, k): dep = op_deps[op_indices[prev_idx]][op_indices[k]] if dep == core.Node.Dep.NoDep: continue # [start_idx, k) is valid groups insert_new_group(op_indices, start_idx, k) start_idx = k break k += 1 insert_new_group(op_indices, start_idx, k) return new_groups def insert_coalesce_tensor_ops(block, coalesce_ops_kwargs): if not coalesce_ops_kwargs: return var_infos = {} for idx, op in enumerate(block.ops): for var in op.input_arg_names: if var not in var_infos: var_infos[var] = [idx, True] for var in op.output_arg_names: if var not in var_infos: var_infos[var] = [idx, False] n = len(block.ops) insert_idx_and_kwargs = [] for group_idx, kwargs in enumerate(coalesce_ops_kwargs): all_vars = kwargs["inputs"]["Input"] + kwargs["outputs"]["Output"] min_op_idx = n copy_data = False for var in all_vars: if var not in var_infos: copy_data = True min_idx = 0 break op_idx, is_input = var_infos[var] if is_input: copy_data = True min_op_idx = min(min_op_idx, op_idx) kwargs["attrs"]["copy_data"] = copy_data insert_idx_and_kwargs.append((min_op_idx, kwargs)) insert_idx_and_kwargs.sort(key=lambda element: element[0], reverse=True) for idx, kwargs in insert_idx_and_kwargs: block._insert_op_without_sync(idx, **kwargs) def insert_fuse_all_reduce_by_memory_size(block, groups, max_memory_size): op_role_key = core.op_proto_and_checker_maker.kOpRoleAttrName() op_role_var_key = core.op_proto_and_checker_maker.kOpRoleVarAttrName() op_device_key = core.op_proto_and_checker_maker.kOpDeviceAttrName() coalesce_ops_kwargs = [] for group in reversed(groups): first_op = block.ops[group[0]] ring_id = first_op.attr("ring_id") use_calc_stream = first_op.attr("use_calc_stream") use_model_parallel = first_op.attr("use_model_parallel") op_role = first_op.attr(op_role_key) op_device = first_op.attr(op_device_key) attrs = { "ring_id": ring_id, "use_calc_stream": use_calc_stream, "use_model_parallel": use_model_parallel, op_role_key: op_role, op_device_key: op_device, } dtype = block._find_var_recursive(first_op.input("X")[0]).dtype sizeof = core.size_of_dtype(dtype) cur_mem_size = 0 op_role_vars = [] recorded_op_indices = [] in_var_names = [] out_var_names = [] for op_idx in reversed(group): op = block.ops[op_idx] in_var_name = op.input("X")[0] out_var_name = op.output("Out")[0] in_var = block._find_var_recursive(in_var_name) mem_size = int(np.prod(in_var.shape)) * sizeof if cur_mem_size + mem_size > max_memory_size: if len(recorded_op_indices) > 1: attrs[op_role_var_key] = op_role_vars coalesce_op_kwargs = insert_fuse_all_reduce_ops( block, recorded_op_indices, in_var_names, out_var_names, dtype, attrs) coalesce_ops_kwargs.append(coalesce_op_kwargs) cur_mem_size = 0 op_role_vars = [] recorded_op_indices = [] in_var_names = [] out_var_names = [] cur_mem_size += mem_size recorded_op_indices.append(op_idx) in_var_names.append(in_var_name) out_var_names.append(out_var_name) if op.has_attr(op_role_var_key): op_role_vars.extend(op.attr(op_role_var_key)) if len(recorded_op_indices) > 1: attrs[op_role_var_key] = op_role_vars coalesce_op_kwargs = insert_fuse_all_reduce_ops( block, recorded_op_indices, in_var_names, out_var_names, dtype, attrs) coalesce_ops_kwargs.append(coalesce_op_kwargs) block._sync_with_cpp() insert_coalesce_tensor_ops(block, coalesce_ops_kwargs) @register_pass("fuse_all_reduce") class FuseAllReducePass(PassBase): def __init__(self): super(FuseAllReducePass, self).__init__() self.set_attr("max_memory_size", -1) def _check_self(self): max_memory_size = self.get_attr("max_memory_size") return max_memory_size > 0 def _check_conflict(self, other_pass): return True def _type(self): return PassType.COMM_OPT # NOTE: why FuseAllReducePass can override apply_single_impl instead of # apply_impl? AllReduce is a collective operation, so the program of each # rank inside the same communication group should have the same # c_allreduce_sum operations. Therefore, FuseAllReducePass can override # apply_single_impl directly. def _apply_single_impl(self, main_program, startup_program, context): max_memory_size = self.get_attr("max_memory_size") op_deps = main_program.desc.get_op_deps() num_blocks = main_program.num_blocks for i in range(num_blocks): block = main_program.block(i) groups = find_all_fuse_all_reduce_groups(block) groups = split_fuse_all_reduce_groups_by_deps( block, groups, op_deps[i]) insert_fuse_all_reduce_by_memory_size(block, groups, max_memory_size) main_program._sync_with_cpp()