DeepLearningExamples/PyTorch/LanguageModeling/BERT/fused_adam_local.py
Przemek Strzelczyk 0663b67c1a Updating models
2019-07-08 22:51:28 +02:00

206 lines
9 KiB
Python

import types
import importlib
import math
import torch
def warmup_cosine(x, warmup=0.002):
if x < warmup:
return x/warmup
return 0.5 * (1.0 + torch.cos(math.pi * x))
def warmup_constant(x, warmup=0.002):
if x < warmup:
return x/warmup
return 1.0
def warmup_linear(x, warmup=0.002):
if x < warmup:
return x/warmup
return 1.0 - x
SCHEDULES = {
'warmup_cosine':warmup_cosine,
'warmup_constant':warmup_constant,
'warmup_linear':warmup_linear,
}
class FusedAdamBert(torch.optim.Optimizer):
"""Implements Adam algorithm. Currently GPU-only. Requires Apex to be installed via
``python setup.py install --cuda_ext --cpp_ext``.
It has been proposed in `Adam: A Method for Stochastic Optimization`_.
Arguments:
params (iterable): iterable of parameters to optimize or dicts defining
parameter groups.
lr (float, optional): learning rate. (default: 1e-3)
betas (Tuple[float, float], optional): coefficients used for computing
running averages of gradient and its square. (default: (0.9, 0.999))
eps (float, optional): term added to the denominator to improve
numerical stability. (default: 1e-8)
weight_decay (float, optional): weight decay (L2 penalty) (default: 0)
amsgrad (boolean, optional): whether to use the AMSGrad variant of this
algorithm from the paper `On the Convergence of Adam and Beyond`_
(default: False) NOT SUPPORTED in FusedAdam!
eps_inside_sqrt (boolean, optional): in the 'update parameters' step,
adds eps to the bias-corrected second moment estimate before
evaluating square root instead of adding it to the square root of
second moment estimate as in the original paper. (default: False)
.. _Adam\: A Method for Stochastic Optimization:
https://arxiv.org/abs/1412.6980
.. _On the Convergence of Adam and Beyond:
https://openreview.net/forum?id=ryQu7f-RZ
"""
# def __init__(self, params,
# lr=1e-3, bias_correction = True,
# betas=(0.9, 0.999), eps=1e-8, eps_inside_sqrt = False,
# weight_decay=0., max_grad_norm=0., amsgrad=False):
def __init__(self, params, lr=1e-3, warmup=-1, t_total=-1, bias_correction=False, betas=(0.9, 0.999), schedule='warmup_linear',
eps=1e-6, eps_inside_sqrt = False, weight_decay=0., max_grad_norm=1.0, amsgrad=False):
global fused_adam_cuda
fused_adam_cuda = importlib.import_module("fused_adam_cuda")
if amsgrad:
raise RuntimeError('FusedAdam does not support the AMSGrad variant.')
defaults = dict(lr=lr, bias_correction=bias_correction,
betas=betas, eps=eps, weight_decay=weight_decay,
max_grad_norm=max_grad_norm)
super(FusedAdamBert, self).__init__(params, defaults)
print("LOCAL FUSED ADAM")
self.eps_mode = 0 if eps_inside_sqrt else 1
self.schedule = schedule
self.t_total = t_total
self.warmup = warmup
def get_lr(self):
lr = []
for group in self.param_groups:
for p in group['params']:
state = self.state[p]
if len(state) == 0:
return [0]
if group['t_total'] != -1:
schedule_fct = SCHEDULES[group['schedule']]
lr_scheduled = group['lr'] * schedule_fct(state['step']/group['t_total'], group['warmup'])
else:
lr_scheduled = group['lr']
lr.append(lr_scheduled)
print("LR {}".format(lr_scheduled))
return lr
def step(self, closure=None, grads=None, output_params=None, scale=1., grad_norms=None):
"""Performs a single optimization step.
Arguments:
closure (callable, optional): A closure that reevaluates the model
and returns the loss.
grads (list of tensors, optional): weight gradient to use for the
optimizer update. If gradients have type torch.half, parameters
are expected to be in type torch.float. (default: None)
output params (list of tensors, optional): A reduced precision copy
of the updated weights written out in addition to the regular
updated weights. Have to be of same type as gradients. (default: None)
scale (float, optional): factor to divide gradient tensor values
by before applying to weights. (default: 1)
"""
loss = None
if closure is not None:
loss = closure()
if grads is None:
grads_group = [None]*len(self.param_groups)
# backward compatibility
# assuming a list/generator of parameter means single group
elif isinstance(grads, types.GeneratorType):
grads_group = [grads]
elif type(grads[0])!=list:
grads_group = [grads]
else:
grads_group = grads
if output_params is None:
output_params_group = [None]*len(self.param_groups)
elif isinstance(output_params, types.GeneratorType):
output_params_group = [output_params]
elif type(output_params[0])!=list:
output_params_group = [output_params]
else:
output_params_group = output_params
if grad_norms is None:
grad_norms = [None]*len(self.param_groups)
#Compute global norm
global_norm = 0.0
for group, grads_this_group, output_params_this_group, grad_norm in zip(self.param_groups, grads_group,
output_params_group, grad_norms):
global_norm = (global_norm ** 2 + grad_norm ** 2) ** 0.5
for group, grads_this_group, output_params_this_group, grad_norm in zip(self.param_groups, grads_group, output_params_group, grad_norms):
if grads_this_group is None:
grads_this_group = [None]*len(group['params'])
if output_params_this_group is None:
output_params_this_group = [None]*len(group['params'])
# compute combined scale factor for this group
combined_scale = scale
if group['max_grad_norm'] > 0:
# norm is in fact norm*scale
clip = ((global_norm / scale) + 1e-6) / group['max_grad_norm']
if clip > 1:
combined_scale = clip * scale
bias_correction = 1 if group['bias_correction'] else 0
for p, grad, output_param in zip(group['params'], grads_this_group, output_params_this_group):
#note: p.grad should not ever be set for correct operation of mixed precision optimizer that sometimes sends None gradients
if p.grad is None and grad is None:
continue
if grad is None:
grad = p.grad.data
if grad.is_sparse:
raise RuntimeError('FusedAdam does not support sparse gradients, please consider SparseAdam instead')
state = self.state[p]
# State initialization
if len(state) == 0:
state['step'] = 0
# Exponential moving average of gradient values
state['exp_avg'] = torch.zeros_like(p.data)
# Exponential moving average of squared gradient values
state['exp_avg_sq'] = torch.zeros_like(p.data)
exp_avg, exp_avg_sq = state['exp_avg'], state['exp_avg_sq']
beta1, beta2 = group['betas']
state['step'] += 1
out_p = torch.tensor([], dtype = torch.float) if output_param is None else output_param
#Changes sharath
schedule_fct = SCHEDULES[self.schedule]
#schedule_fct(state['step']/self.t_total, self.warmup)
#step_lr = group['lr'] * schedule_fct(state['step']/self.t_total, self.warmup)
#step_lr = group['lr'] * scale#schedule_fct(state['step']/self.t_total, self.warmup)# schedule_fct(state['step']/group['t_total'], group['warmup'])
#print(scale, step_lr)
#print(group['lr'])
fused_adam_cuda.adam(p.data,
out_p,
exp_avg,
exp_avg_sq,
grad,
group['lr'], #step_lr,#group['lr'],
beta1,
beta2,
group['eps'],
combined_scale,
state['step'],
self.eps_mode,
bias_correction,
group['weight_decay'])
return loss