schedule_3x.py

# Copyright (c) OpenMMLab. All rights reserved.
from mmengine.optim.optimizer.optimizer_wrapper import OptimWrapper
from mmengine.optim.scheduler.lr_scheduler import MultiStepLR
from mmengine.runner.loops import EpochBasedTrainLoop, TestLoop, ValLoop
from torch.optim.adamw import AdamW

# optimizer
# This schedule is mainly used by models on indoor dataset,
# e.g., VoteNet on SUNRGBD and ScanNet
lr = 0.008  # max learning rate
optim_wrapper = dict(
    type=OptimWrapper,
    optimizer=dict(type=AdamW, lr=lr, weight_decay=0.01),
    clip_grad=dict(max_norm=10, norm_type=2),
)

# training schedule for 3x
train_cfg = dict(type=EpochBasedTrainLoop, max_epochs=36, val_interval=1)
val_cfg = dict(type=ValLoop)
test_cfg = dict(type=TestLoop)

# learning rate
param_scheduler = [
    dict(
        type=MultiStepLR,
        begin=0,
        end=36,
        by_epoch=True,
        milestones=[24, 32],
        gamma=0.1)
]

# Default setting for scaling LR automatically
#   - `enable` means enable scaling LR automatically
#       or not by default.
#   - `base_batch_size` = (4 GPUs) x (8 samples per GPU).
auto_scale_lr = dict(enable=False, base_batch_size=32)