mirror of
https://github.com/wassname/pytorch-lightning.git
synced 2026-09-23 13:40:39 +08:00
Jirka BorovecandWilliam Falcon
ff1f8ef400
* till 0.8 * refactor * fix tests * fix tests * deprx till 0.9 * Update trainer.py * Apply suggestions from code review Co-authored-by: William Falcon <waf2107@columbia.edu>
61 lines
2.1 KiB
Python
61 lines
2.1 KiB
Python
r"""
|
|
Gradient Accumulator
|
|
====================
|
|
Change gradient accumulation factor according to scheduling.
|
|
"""
|
|
|
|
import warnings
|
|
|
|
from .base import Callback
|
|
|
|
|
|
class GradientAccumulationScheduler(Callback):
|
|
r"""
|
|
Change gradient accumulation factor according to scheduling.
|
|
|
|
Args:
|
|
scheduling: scheduling in format {epoch: accumulation_factor}
|
|
.. warning:: Epochs indexing starts from "1" until v0.6.x,
|
|
but will start from "0" in v0.8.0.
|
|
|
|
Example::
|
|
|
|
from pytorch_lightning import Trainer
|
|
from pytorch_lightning.callbacks import GradientAccumulationScheduler
|
|
|
|
# at epoch 5 start accumulating every 2 batches
|
|
accumulator = GradientAccumulationScheduler(scheduling: {5: 2})
|
|
Trainer(accumulate_grad_batches=accumulator)
|
|
"""
|
|
|
|
def __init__(self, scheduling: dict):
|
|
super().__init__()
|
|
|
|
if not scheduling: # empty dict error
|
|
raise TypeError("Empty dict cannot be interpreted correct")
|
|
|
|
for key in scheduling:
|
|
if not isinstance(key, int) or not isinstance(scheduling[key], int):
|
|
raise TypeError("All epoches and accumulation factor must be integers")
|
|
|
|
minimal_epoch = min(scheduling.keys())
|
|
warnings.warn('Epochs indexing of `scheduling` starts from "1" until v0.6.x,'
|
|
' but will start from "0" in v0.8.0.', DeprecationWarning)
|
|
if minimal_epoch < 1:
|
|
msg = f"Epochs indexing from 1, epoch {minimal_epoch} cannot be interpreted correct"
|
|
raise IndexError(msg)
|
|
if minimal_epoch != 1: # if user didnt define first epoch accumulation factor
|
|
scheduling.update({1: 1})
|
|
|
|
self.scheduling = scheduling
|
|
self.epochs = sorted(scheduling.keys())
|
|
|
|
def on_epoch_start(self, trainer, pl_module):
|
|
# indexing epochs from 1 (until v0.6.x)
|
|
# In v0.8.0, ` + 1` should be removed.
|
|
epoch = trainer.current_epoch + 1
|
|
for i in reversed(range(len(self.epochs))):
|
|
if epoch >= self.epochs[i]:
|
|
trainer.accumulate_grad_batches = self.scheduling.get(self.epochs[i])
|
|
break
|