ColossalAI/colossalai/pipeline/utils.py

276 lines
8.8 KiB
Python

import heapq
import inspect
import torch
from colossalai.logging import get_dist_logger
from colossalai.nn.layer.utils import CheckpointModule
from typing import List
from collections import OrderedDict
def _binary_partition(weights: List, start: int, end: int):
"""Returns the binary partition position of `weights`, given the start
position `st` and the end position `ed`.
Args:
weights (list): A python list to be binary partitioned
start (int): the start position of the binary partition
end (int): the end position of the binary partition
Returns:
int: the binary partition position of `weights`
"""
w_sum = weights[end - 1]
prefix = 0
if start > 0:
w_sum -= weights[start - 1]
prefix = weights[start - 1]
minimum = float("inf")
for idx in range(start + 1, end):
front = weights[idx - 1] - prefix
diff = abs(w_sum - 2 * front)
if diff < minimum:
pos = idx
minimum = diff
return start, pos, end
def _heap_addition(weights: List, intervals: int, add_cnt: int):
"""
"""
def _heap_push(heap, st, ed):
value = weights[ed - 1]
if st > 0:
value -= weights[st - 1]
heapq.heappush(heap, (-value, st, ed))
ret_intervals = []
heap = []
for st, ed in intervals:
_heap_push(heap, st, ed)
while add_cnt > 0:
_, st, ed = heapq.heappop(heap)
if ed - st == 1:
ret_intervals.append((st, ed))
else:
l, m, r = _binary_partition(weights, st, ed)
_heap_push(heap, l, m)
_heap_push(heap, m, r)
add_cnt -= 1
while heap:
_, st, ed = heapq.heappop(heap)
ret_intervals.append((st, ed))
ret_intervals.sort()
return ret_intervals
def _calc_partitions(weights, value):
prev = 0
prefix = 0
num_block = 0
intervals = []
for idx, w in enumerate(weights):
if weights[idx] - prefix > value:
intervals.append((prev, idx))
prev = idx
prefix = weights[idx - 1]
num_block += 1
intervals.append((prev, len(weights)))
return num_block + 1, intervals
def _binary_search(weights, num):
length = len(weights)
prefix = [1 if w == 0 else w for w in weights]
for i in range(1, length):
prefix[i] += prefix[i - 1]
lower_bound = max(weights)
upper_bound = prefix[length - 1]
while upper_bound > lower_bound:
mid = (upper_bound + lower_bound) // 2
number, _ = _calc_partitions(prefix, mid)
if number <= num:
upper_bound = mid
else:
lower_bound = mid + 1
num_block, intervals = _calc_partitions(prefix, upper_bound)
if num_block < num:
intervals = _heap_addition(prefix, intervals, num - num_block)
return intervals
def partition_uniform(num_items, pipeline_parallel_size, num_chunks):
assert num_items % num_chunks == 0, \
"Layer length should be divided by the number of chunks, otherwise parameter method is recomended"
logger = get_dist_logger()
parts = [[] for _ in range(pipeline_parallel_size)]
partition_items = num_items // num_chunks
for idx in range(num_chunks):
base_idx = idx * partition_items
chunk_size = partition_items // pipeline_parallel_size
left = pipeline_parallel_size - partition_items % pipeline_parallel_size
if chunk_size == 0:
logger.warning("Some nodes in Pipeline have no requests")
for p in range(pipeline_parallel_size):
st = base_idx
base_idx += chunk_size + (p >= left)
parts[p].append((st, base_idx))
return parts
def partition_balanced(weights, pipeline_parallel_size, num_chunks):
num_total = pipeline_parallel_size * num_chunks
num_items = len(weights)
if num_items <= num_total:
return partition_uniform(num_items, pipeline_parallel_size, num_chunks)
intervals = _binary_search(weights, num_total)
current = 0
parts = [[] for _ in range(pipeline_parallel_size)]
for inter in intervals:
parts[current].append(inter)
current = (current + 1) % pipeline_parallel_size
return parts
def build_kwargs_for_module(function, input_tensor, kw_dict):
"""
Generally, the first argument of module.forward is an input tensor come from the previous layer.
Therefore, we just filter the kwargs from second element of the dictionary.
"""
sig = inspect.signature(function)
if input_tensor is None:
kwargs_offset = 0
elif isinstance(input_tensor, torch.Tensor):
kwargs_offset = 1
elif isinstance(input_tensor, (tuple, OrderedDict)):
#assert isinstance(input_tensor, tuple), f'input_tensor should be a torch.Tensor or a tuple object.'
# Huggingface will take their own structures based on OrderedDict as the output
# between layers so we've to close this check.
kwargs_offset = len(input_tensor)
args_name_list = list(sig.parameters.keys())
kw_dict = {k: v for k, v in kw_dict.items() if k in args_name_list[kwargs_offset:]}
if len(kw_dict) == 0:
return None
return kw_dict
def build_kwargs_for_function(function, kw_dict):
sig = inspect.signature(function)
kw_dict = {k: v for k, v in kw_dict.items() if k in sig.parameters}
if len(kw_dict) == 0:
return None
return kw_dict
def exec_func_with_kwargs(func, kw_dict, input_tensor, kwargs):
"""
We suppose the callable object passed to to_layer_list method in two purpose:
a. use the callable object to modify input tensor, such as \
lambda x: torch.flatten(x, 1)
b. use the callable object to modify kwargs value, such as \
def foo(attention_mask=None):
if attention_mask is not None:
batch_size = input_ids.shape[0]
attention_mask = attention_mask.view(batch_size, -1)
return attention_mask
"""
if kw_dict is not None:
rst = func(**kw_dict)
if isinstance(rst, tuple):
for i, k in enumerate(kw_dict.keys()):
kwargs[k] = rst[i]
else:
for k in kw_dict.keys():
kwargs[k] = rst
return input_tensor
if isinstance(input_tensor, tuple):
assert len(input_tensor) > 0, f'input_tensor should not be empty, when kw_dict is None.'
sig = inspect.signature(func)
func_args_num = len(sig.parameters)
assert func_args_num <= len(
input_tensor), f'func requires {func_args_num} arguments, but input_tensors only have {len(input_tensor)}.'
if func_args_num < len(input_tensor):
return func(*input_tensor[:func_args_num])
else:
return func(*input_tensor)
assert isinstance(input_tensor, torch.Tensor), 'input_tensor should be a type of torch.Tensor or tuple.'
return func(input_tensor)
def exec_funcs_with_kwargs(func_dict, func_key, input_tensor, kwargs):
assert func_key in func_dict, f"{func_key} is not in the function_dict."
funcs_to_exec = func_dict[func_key]
if isinstance(funcs_to_exec, list):
for f in funcs_to_exec:
f_kwargs = build_kwargs_for_function(f, kwargs)
input_tensor = exec_func_with_kwargs(f, f_kwargs, input_tensor, kwargs)
else:
f_kwargs = build_kwargs_for_function(funcs_to_exec, kwargs)
input_tensor = exec_func_with_kwargs(funcs_to_exec, f_kwargs, input_tensor, kwargs)
return input_tensor
def call_module(module, args=None, kwargs=None):
if args is None:
args = ()
if kwargs is None:
kwargs = {}
if isinstance(module, CheckpointModule):
forward_func = module._forward
else:
forward_func = module.forward
sig = inspect.signature(forward_func)
param_nums = len(sig.parameters)
feed_nums = len(args) + len(kwargs)
args_needed_nums = param_nums - len(kwargs)
args_needed = args[:args_needed_nums]
if isinstance(module, CheckpointModule):
convert_kwargs_to_args = []
for v in kwargs.values():
convert_kwargs_to_args.append(v)
return module(*args_needed, *convert_kwargs_to_args)
else:
return module(*args_needed, **kwargs)
def customized_partition(exec_seq):
'''
This function will analyze the exec_seq. In the exec_seq, users will use 'SPLIT_NODE' as an
annotation to note the partition point.
'''
customized_parts = {}
start = 0
stop = 0
rank = 0
for element in exec_seq:
if isinstance(element, str):
if element == 'SPLIT_NODE':
customized_parts[rank] = [(start, stop)]
start = stop
rank += 1
else:
stop += 1
customized_parts[rank] = [(start, stop)]
return customized_parts