def prune_by_percentile(percent,
resample=False,
reinit=False,
total_params=1,
hessian_aware=False,
criterion=None,
dataloader=None,
cuda=True,
**kwargs):
global step
global mask
global model
traces = {}
print("Start Hessian Computing")
if hessian_aware:
model.eval()
hessian_comp = hessian(model, criterion, data=dataloader, cuda=cuda)
for name, param in model.named_parameters():
param_frac = param.numel() / total_params
if 'weight' in name and param_frac > 0.01:
traces[name] = hessian_comp.trace(name)
print("Trace for layer:{} is {}".format(name, traces[name]))
traces_thres = np.mean(np.array(list(traces.values())))
for name, trace in traces.items():
traces[name] = np.mean(trace) >= traces_thres
# Calculate percentile value
step = 0
for name, param in model.named_parameters():
# We do not prune bias term
if 'weight' in name: # each layer
param_frac = param.numel() / total_params
if param_frac > 0.01:
tensor = param.data.cpu().numpy()
alive = tensor[np.nonzero(
tensor)] # flattened array of nonzero values
if hessian:
if traces[name]:
hess_percent = percent / 2
else:
hess_percent = min(percent * 2, 30)
print("Hessian-aware pruning percent for layer:{} is {}".
format(name, hess_percent))
percentile_value = np.percentile(abs(alive), hess_percent)
else:
percentile_value = np.percentile(abs(alive), percent)
# Convert Tensors to numpy and calculate
weight_dev = param.device
new_mask = np.where(
abs(tensor) < percentile_value, 0, mask[step])
# Apply new weight and mask
param.data = torch.from_numpy(tensor * new_mask).to(
weight_dev) # zero out
mask[step] = new_mask
step += 1
step = 0
def get_hessian(model, dataset_name, batch_size):
"""
This function creates a Pyhessian object given which can be used to compute top_n
eigenvalues, density or trace of the hessian of the model
Args:
model: nn.Module
dataset_name: name of the dataset used to train the model
batch_size: size of the batch used to create the Pyhessian object
Returns:
model_hessian: Pyhessian object
inputs: inputs used to create model_hesssian
targets: targets used to create model_hesssian
criterion: loss criterion
"""
# Work with only one (big) batch
train_loader, _ = utils.load_data("/home/app/datasets",
batch_size=batch_size,
dataset=dataset_name)
inputs, targets = next(iter(train_loader))
criterion = torch.nn.CrossEntropyLoss()
model_hessian = hessian(model,
criterion,
data=(inputs, targets),
cuda=False)
return model_hessian, inputs, targets, criterion
def get_models_trace(models,
data_loader,
criterion,
full_dataset=False,
verbose=False,
device=None):
trace_dict = {}
hessian_dataloader = []
for i, (inputs, labels) in enumerate(data_loader):
hessian_dataloader.append((inputs, labels))
if not full_dataset:
break
# get trace
for k, m in models.items():
if verbose:
print(k)
a = time.time()
ts = []
if device is not None:
m = m.to(device)
is_gpu = True
else:
is_gpu = False
if full_dataset:
trace = hessian(m,
criterion,
dataloader=hessian_dataloader,
cuda=is_gpu).trace()
else:
trace = hessian(m,
criterion,
data=hessian_dataloader[0],
cuda=is_gpu).trace()
trace_dict[k] = trace
return trace_dict
def GetHessianEig(path, hessian_dataloader):
criterion = nn.CrossEntropyLoss() # label loss
# get model
model = MLP()
if args.cuda:
model = model.cuda()
model = torch.nn.DataParallel(model)
check_point = torch.load(path)
model.load_state_dict(check_point.state_dict)
######################################################
# Begin the computation
######################################################
# turn model to eval mode
model.eval()
if batch_num == 1:
hessian_comp = hessian(model,
criterion,
data=hessian_dataloader,
cuda=args.cuda)
else:
hessian_comp = hessian(model,
criterion,
dataloader=hessian_dataloader,
cuda=args.cuda)
print(
'********** finish data londing and begin Hessian computation **********')
top_eigenvalues, _ = hessian_comp.eigenvalues(top_n=3)
return top_eigenvalues
# Get model checkpoint, get saving folder
###################
if args.resume == '':
raise Exception("please choose the trained model")
model.load_state_dict(torch.load(args.resume))
######################################################
# Begin the computation
######################################################
# turn model to eval mode
model.eval()
if batch_num == 1:
hessian_comp = hessian(model,
criterion,
data=hessian_dataloader,
cuda=args.cuda,
record_data=True)
else:
hessian_comp = hessian(model,
criterion,
dataloader=hessian_dataloader,
cuda=args.cuda,
record_data=True)
print(
'********** finish data loading and begin Hessian computation **********')
print("Computing eigenvalues...")
top_eigenvalues, _ = hessian_comp.eigenvalues(top_n=20, debug=True)
print("Computing trace...")
# for k, v in state_dict.items():
# name = k[7:]
# new_state_dict[name] = v
model.load_state_dict(torch.load(args.resume + '/' + files[file_index]))
######################################################
# Begin the computation
######################################################
# turn model to eval mode
model.eval()
if batch_num == 1:
hessian_comp = hessian(model,
criterion,
data=hessian_dataloader,
cuda=args.cuda)
else:
hessian_comp = hessian(model,
criterion,
dataloader=hessian_dataloader,
cuda=args.cuda)
print(
'********** finish data londing and begin Hessian computation **********'
)
print('now is for the whole model')
top_eigenvalues, _ = hessian_comp.eigenvalues()
trace = hessian_comp.trace()
density_eigen, density_weight = hessian_comp.density()
###################
# Get model checkpoint, get saving folder
###################
if args.resume == '':
raise Exception("please choose the trained model")
model.load_state_dict(torch.load(args.resume))
######################################################
# Begin the computation
######################################################
# turn model to eval mode
model.eval()
if batch_num == 1:
hessian_comp = hessian(model,
criterion,
data=hessian_dataloader,
cuda=args.cuda)
else:
hessian_comp = hessian(model,
criterion,
dataloader=hessian_dataloader,
cuda=args.cuda)
print(
'********** finish data londing and begin Hessian computation **********')
top_eigenvalues, _ = hessian_comp.eigenvalues()
trace = hessian_comp.trace()
density_eigen, density_weight = hessian_comp.density()
print('\n***Top Eigenvalues: ', top_eigenvalues)
def _hard_training_step(nets,
nets_weights,
net_optimizers,
net_data_loaders,
criterion,
weight_type,
var_noise=None,
curr_step=0,
writer=None,
device=None,
hard_train_eps=None):
"""Does update step on all networks and computes the weights.
If wanting to do a random walk, set learning rate of net_optimizer to zero and set var_noise to noise level."""
taking_step = True
steps_taken = 0
mean_loss = 0
curr_loss = float("inf")
assert not (hard_train_eps and (len(nets) > 0))
continue_training = True
for idx_net in range(len(nets)):
# get net and optimizer
net = nets[idx_net]
optimizer = net_optimizers[idx_net]
# get the inputs; data is a list of [inputs, labels]
try:
data = next(net_data_loaders[idx_net])
except:
taking_step = False
break
inputs, labels = data
if device is not None:
inputs, labels = inputs.to(device).type(
torch.cuda.FloatTensor), labels.to(device).type(
torch.cuda.LongTensor)
while continue_training:
# Compute gradients for input.
inputs.requires_grad = True
# zero the parameter gradients
optimizer.zero_grad()
# forward + backward + optimize
outputs = net(inputs)
loss = criterion(outputs, labels)
loss.backward(retain_graph=True)
optimizer.step()
if var_noise is not None:
with torch.no_grad():
for param in net.parameters():
param.add_(torch.randn(param.size()) * var_noise)
# update weights
param_grads = get_grad_params_vec(net)
curr_weight = torch.norm(param_grads)
nets_weights[idx_net] += curr_weight
# store metrics for each net
if writer is not None:
writer.add_scalar('Loss/train/net_{}'.format(idx_net), loss,
curr_step)
writer.add_scalar('Potential/curr/net_{}'.format(idx_net),
curr_weight, curr_step)
writer.add_scalar('Norm/net_{}'.format(idx_net),
torch.norm(get_params_vec(net)), curr_step)
if (curr_step % 50) == 0:
# a = time.time()
is_gpu = device is not None
trace = np.mean(
hessian(net,
criterion,
data=(inputs, labels),
cuda=is_gpu).trace())
writer.add_scalar('Trace/net_{}'.format(idx_net), trace,
curr_step)
# print("Getting trace took {}".format(time.time() - a))
mean_loss += float(loss)
steps_taken += 1
curr_step += 1
continue_training = float(loss) > hard_train_eps
assert taking_step or (idx_net == 0)
return nets, nets_weights, steps_taken, mean_loss / steps_taken
def training_step(nets,
nets_weights,
net_optimizers,
net_data_loaders,
criterion,
weight_type,
var_noise=None,
curr_step=0,
writer=None,
device=None):
"""Does update step on all networks and computes the weights.
If wanting to do a random walk, set learning rate of net_optimizer to zero and set var_noise to noise level."""
taking_step = True
steps_taken = 0
mean_loss = 0
for idx_net in range(len(nets)):
# get net and optimizer
net = nets[idx_net]
optimizer = net_optimizers[idx_net]
# get the inputs; data is a list of [inputs, labels]
try:
data = next(net_data_loaders[idx_net])
except:
taking_step = False
break
inputs, labels = data
if device is not None:
inputs, labels = inputs.to(device).type(
torch.cuda.FloatTensor), labels.to(device).type(
torch.cuda.LongTensor)
# Compute gradients for input.
inputs.requires_grad = True
# zero the parameter gradients
optimizer.zero_grad()
# forward + backward + optimize
outputs = net(inputs)
loss = criterion(outputs, labels)
loss.backward(retain_graph=True)
optimizer.step()
if var_noise is not None:
with torch.no_grad():
for param in net.parameters():
noise = torch.randn(param.size()) * var_noise
if device is not None:
noise = noise.to(device)
param.add_(noise)
# update weights
if weight_type == "input_output_forbenius":
# zero the parameter
optimizer.zero_grad()
# get input gradients
output_forb = torch.norm(outputs)
output_forb.backward()
input_grads = inputs.grad
curr_weight = weight_function_input_jacobian(input_grads)
nets_weights[idx_net] += curr_weight
elif weight_type == "loss_gradient_weights":
param_grads = get_grad_params_vec(net)
curr_weight = torch.norm(param_grads)
nets_weights[idx_net] += curr_weight
elif weight_type is None:
pass
else:
raise NotImplementedError()
# store metrics for each net
if writer is not None:
writer.add_scalar('Loss/train/net_{}'.format(idx_net), loss,
curr_step)
writer.add_scalar('Potential/curr/net_{}'.format(idx_net),
curr_weight, curr_step)
writer.add_scalar('Potential/total/net_{}'.format(idx_net),
nets_weights[idx_net], curr_step)
writer.add_scalar('Norm/net_{}'.format(idx_net),
torch.norm(get_params_vec(net)), curr_step)
if (curr_step % 50) == 0:
# a = time.time()
is_gpu = device is not None
trace = np.mean(
hessian(net, criterion, data=(inputs, labels),
cuda=is_gpu).trace())
writer.add_scalar('Trace/net_{}'.format(idx_net), trace,
curr_step)
# print("Getting trace took {}".format(time.time() - a))
mean_loss += float(loss)
assert taking_step or (idx_net == 0)
return nets, nets_weights, 1 * taking_step, mean_loss / len(nets)
