ColossalAI/colossalai/auto_parallel/solver/strategy/output_generator.py

60 lines
2.1 KiB
Python

import operator
from functools import reduce
from ..sharding_strategy import ShardingStrategy_V2, TrainCycleItem, MemoryCost
from colossalai.tensor.shape_consistency import CollectiveCommPattern
from .strategy_generator import OutputStrategyGenerator
from typing import List
from .._utils import exception_handler
import copy
__all__ = ['OutputGenerator']
class OutputGenerator(OutputStrategyGenerator):
"""
OutputGenerator is a generic class to generate strategies for Output Node.
"""
def validate(self) -> bool:
return super().validate()
def update_compute_cost(self, strategy: ShardingStrategy_V2):
compute_cost = TrainCycleItem(fwd=10, bwd=10, total=20)
strategy.compute_cost = compute_cost
def update_memory_cost(self, strategy: ShardingStrategy_V2):
'''
Compute the memory cost per device with this specific strategy.
'''
fwd_mem_cost = MemoryCost(activation=0, parameter=0)
bwd_mem_cost = MemoryCost(activation=0, parameter=0)
# compute total cost
total_mem_cost = MemoryCost(activation=0, parameter=0)
memory_cost = TrainCycleItem(fwd=fwd_mem_cost, bwd=bwd_mem_cost, total=total_mem_cost)
strategy.memory_cost = memory_cost
def generate(self):
dim_partition_dict_mapping = {
"output": {},
}
for index, _ in enumerate(self.predecessor_nodes):
mapping_name = f"input_{index}"
dim_partition_dict_mapping[mapping_name] = {}
communication_action_mapping = {}
sharding_spec_mapping = self.to_sharding_spec_mapping(dim_partition_dict_mapping)
name = f'Replica Output'
strategy = self.get_sharding_strategy(name=name,
sharding_spec_mapping=sharding_spec_mapping,
communication_action_mapping=communication_action_mapping)
self.update_communication_cost(strategy)
self.update_compute_cost(strategy)
self.update_memory_cost(strategy)
return [strategy]