def create_optimizer(args, model, filter_bias_and_bn=True):
opt_lower = args.opt.lower()
weight_decay = args.weight_decay
if 'adamw' in opt_lower or 'radam' in opt_lower:
# Compensate for the way current AdamW and RAdam optimizers apply LR to the weight-decay
# I don't believe they follow the paper or original Torch7 impl which schedules weight
# decay based on the ratio of current_lr/initial_lr
weight_decay /= args.lr
if weight_decay and filter_bias_and_bn:
parameters = add_weight_decay(model, weight_decay)
weight_decay = 0.
else:
parameters = model.parameters()
if 'fused' in opt_lower:
assert has_apex and torch.cuda.is_available(
), 'APEX and CUDA required for fused optimizers'
opt_split = opt_lower.split('_')
opt_lower = opt_split[-1]
if opt_lower == 'sgd' or opt_lower == 'nesterov':
optimizer = optim.SGD(parameters,
lr=args.lr,
momentum=args.momentum,
weight_decay=weight_decay,
nesterov=True)
elif opt_lower == 'momentum':
optimizer = optim.SGD(parameters,
lr=args.lr,
momentum=args.momentum,
weight_decay=weight_decay,
nesterov=False)
elif opt_lower == 'adam':
optimizer = optim.Adam(parameters,
lr=args.lr,
weight_decay=weight_decay,
eps=args.opt_eps)
elif opt_lower == 'adamw':
optimizer = AdamW(parameters,
lr=args.lr,
weight_decay=weight_decay,
eps=args.opt_eps)
elif opt_lower == 'nadam':
optimizer = Nadam(parameters,
lr=args.lr,
weight_decay=weight_decay,
eps=args.opt_eps)
elif opt_lower == 'radam':
optimizer = RAdam(parameters,
lr=args.lr,
weight_decay=weight_decay,
eps=args.opt_eps)
elif opt_lower == 'adamp':
optimizer = AdamP(parameters,
lr=args.lr,
weight_decay=weight_decay,
eps=args.opt_eps,
delta=0.1,
wd_ratio=0.01,
nesterov=True)
elif opt_lower == 'sgdp':
optimizer = SGDP(parameters,
lr=args.lr,
momentum=args.momentum,
weight_decay=weight_decay,
eps=args.opt_eps,
nesterov=True)
elif opt_lower == 'adadelta':
optimizer = optim.Adadelta(parameters,
lr=args.lr,
weight_decay=weight_decay,
eps=args.opt_eps)
elif opt_lower == 'rmsprop':
optimizer = optim.RMSprop(parameters,
lr=args.lr,
alpha=0.9,
eps=args.opt_eps,
momentum=args.momentum,
weight_decay=weight_decay)
elif opt_lower == 'rmsproptf':
optimizer = RMSpropTF(parameters,
lr=args.lr,
alpha=0.9,
eps=args.opt_eps,
momentum=args.momentum,
weight_decay=weight_decay)
elif opt_lower == 'novograd':
optimizer = NovoGrad(parameters,
lr=args.lr,
weight_decay=weight_decay,
eps=args.opt_eps)
elif opt_lower == 'nvnovograd':
optimizer = NvNovoGrad(parameters,
lr=args.lr,
weight_decay=weight_decay,
eps=args.opt_eps)
elif opt_lower == 'fusedsgd':
optimizer = FusedSGD(parameters,
lr=args.lr,
momentum=args.momentum,
weight_decay=weight_decay,
nesterov=True)
elif opt_lower == 'fusedmomentum':
optimizer = FusedSGD(parameters,
lr=args.lr,
momentum=args.momentum,
weight_decay=weight_decay,
nesterov=False)
elif opt_lower == 'fusedadam':
optimizer = FusedAdam(parameters,
lr=args.lr,
adam_w_mode=False,
weight_decay=weight_decay,
eps=args.opt_eps)
elif opt_lower == 'fusedadamw':
optimizer = FusedAdam(parameters,
lr=args.lr,
adam_w_mode=True,
weight_decay=weight_decay,
eps=args.opt_eps)
elif opt_lower == 'fusedlamb':
optimizer = FusedLAMB(parameters,
lr=args.lr,
weight_decay=weight_decay,
eps=args.opt_eps)
elif opt_lower == 'fusednovograd':
optimizer = FusedNovoGrad(parameters,
lr=args.lr,
betas=(0.95, 0.98),
weight_decay=weight_decay,
eps=args.opt_eps)
else:
assert False and "Invalid optimizer"
raise ValueError
if len(opt_split) > 1:
if opt_split[0] == 'lookahead':
optimizer = Lookahead(optimizer)
return optimizer