ColossalAI/colossalai/pipeline/weight_grad_store.py

107 lines
4.5 KiB
Python

import queue
# from megatron import get_args
# from megatron.core import parallel_state
# from megatron.core.distributed.finalize_model_grads import _allreduce_embedding_grads
# from megatron.core.utils import get_model_config, get_attr_wrapped_model
class WeightGradStore:
cache = []
weight_grad_queue = [queue.Queue(), queue.Queue()]
@classmethod
def put(cls, total_input, grad_output, weight, func):
# func(total_input, grad_output, weight.main_grad)
cls.cache.append((total_input, grad_output, weight, func))
@classmethod
def flush(cls, chunk=0):
cls.weight_grad_queue[chunk].put(cls.cache)
cls.cache = []
@classmethod
def pop(cls, chunk=0):
if cls.weight_grad_queue[chunk].qsize() > 0:
stored_grads = cls.weight_grad_queue[chunk].get()
for total_input, grad_output, weight, func in stored_grads:
if weight.grad is not None:
func(total_input, grad_output, weight.grad)
# for first bwd; weight.grad is None, assign grad_weight to weight.grad
else:
grad_weight = func(total_input, grad_output)
weight.grad = grad_weight
else:
raise Exception("Pop empty queue.")
# @classmethod
# def clear(cls, model, chunk=0):
# weight_grad_tasks = []
# while cls.weight_grad_queue[chunk].qsize() > 0:
# stored_grads = cls.weight_grad_queue[chunk].get()
# if len(weight_grad_tasks) == 0:
# for _ in stored_grads:
# weight_grad_tasks.append([])
# else:
# assert len(weight_grad_tasks) == len(stored_grads)
# for i, task in enumerate(stored_grads):
# weight_grad_tasks[i].append(task)
# weight_params = []
# handles = []
# if get_args().overlap_grad_reduce:
# handles += model.async_reduce_grad()
# output_layer_weight = None
# if parallel_state.is_pipeline_last_stage():
# assert len(weight_grad_tasks) > 0
# output_layer_grads = weight_grad_tasks[0]
# for j in range(len(output_layer_grads)):
# total_input, grad_output, weight, func = output_layer_grads[j]
# if output_layer_weight is None:
# output_layer_weight = weight
# assert output_layer_weight is weight
# func(total_input, grad_output, weight.main_grad)
# output_layer_grads[j] = None # release memory
# weight_grad_tasks = weight_grad_tasks[1:]
# if get_args().overlap_grad_reduce:
# handles += model.async_reduce_grad(output_layer_weight)
# if parallel_state.is_pipeline_first_stage() or parallel_state.is_pipeline_last_stage():
# model_module = get_attr_wrapped_model(model, 'pre_process', return_model_obj=True)
# if model_module.share_embeddings_and_output_weights:
# # if share_embeddings_and_output_weights, wait all-reduce for embeddings
# for handle in handles:
# if handle is not None:
# handle.wait()
# handles = []
# config = get_model_config(model)
# # Do async all-reduce for embedding grads firstly, so that the rank 0 won't
# # be blocked
# embedding_handles = _allreduce_embedding_grads([model], config, async_op=True)
# handles += embedding_handles
# for i in range(len(weight_grad_tasks)):
# tasks = weight_grad_tasks[i]
# param = None
# for j in range(len(tasks)):
# total_input, grad_output, weight, func = tasks[j]
# if param is None:
# param = weight
# assert param is weight
# assert not (weight is output_layer_weight)
# func(total_input, grad_output, weight.main_grad)
# tasks[j] = None # release memory
# weight_params.append(param)
# if get_args().overlap_grad_reduce:
# # All-reduce param grad here
# handles += model.async_reduce_grad(param)
# weight_grad_tasks[i] = None # release memory
# # timers('wait_all_reduce', log_level=1).start(barrier=False)
# for handle in embedding_handles:
# if handle is not None:
# handle.wait()
# # timers('wait_all_reduce').stop()