# megengine.jit.sublinear_memory_config 源代码

# -*- coding: utf-8 -*-
#
#
# Unless required by applicable law or agreed to in writing,
# "AS IS" BASIS, WITHOUT ARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
from ..device import get_device_count

[文档]class SublinearMemoryConfig:
r"""
Configuration for sublinear memory optimization.

:param thresh_nr_try: number of samples both for searching in linear space
and around current thresh in sublinear memory optimization. Default: 10.
It can also be set through the environmental variable 'MGB_SUBLINEAR_MEMORY_THRESH_NR_TRY'.
:param genetic_nr_iter: number of iterations to find the best checkpoints in genetic algorithm.
Default: 0.
It can also be set through the environmental variable 'MGB_SUBLINEAR_MEMORY_GENETIC_NR_ITER'.
:param genetic_pool_size: number of samples for the crossover random selection
during genetic optimization. Default: 20.
It can also be set through the environmental variable 'MGB_SUBLINEAR_MEMORY_GENETIC_POOL_SIZE'.
:param lb_memory: memory lower bound of bottleneck size in MB for sublinear memory optimization.
It can be used to perform manual tradeoff between memory and speed. Default: 0.
It can also be set through the environmental variable 'MGB_SUBLINEAR_MEMORY_LOWER_BOUND_MB'.
:param num_worker: number of thread workers to search the optimum checkpoints
in sublinear memory optimization. Default: half of cpu number in the system.
Note: the value must be greater or equal to one.
It can also be set through the environmental variable 'MGB_SUBLINEAR_MEMORY_WORKERS'.

Note that the environmental variable MGB_COMP_GRAPH_OPT must be set to 'enable_sublinear_memory_opt=1'
in order for the above environmental variable to be effective.
"""

def __init__(
self,
thresh_nr_try: int = 10,
genetic_nr_iter: int = 0,
genetic_pool_size: int = 20,
lb_memory: int = 0,
num_worker: int = max(1, get_device_count("cpu") // 2),
):
assert thresh_nr_try >= 0, "thresh_nr_try must be greater or equal to zero"
self.thresh_nr_try = thresh_nr_try
assert genetic_nr_iter >= 0, "genetic_nr_iter must be greater or equal to zero"
self.genetic_nr_iter = genetic_nr_iter
assert (
genetic_pool_size >= 0
), "genetic_pool_size must be greater or equal to zero"
self.genetic_pool_size = genetic_pool_size
self.lb_memory = lb_memory
assert num_worker > 0, "num_worker must be greater or equal to one"
self.num_worker = num_worker