xautodl/exps/NAS-Bench-201-algos/DARTS-V2.py
2021-10-04 00:53:35 -07:00

497 lines
18 KiB
Python

##################################################
# Copyright (c) Xuanyi Dong [GitHub D-X-Y], 2020 #
########################################################
# DARTS: Differentiable Architecture Search, ICLR 2019 #
########################################################
import os, sys, time, glob, random, argparse
import numpy as np
from copy import deepcopy
import torch
import torch.nn as nn
from xautodl.config_utils import load_config, dict2config, configure2str
from xautodl.datasets import get_datasets, get_nas_search_loaders
from xautodl.procedures import (
prepare_seed,
prepare_logger,
save_checkpoint,
copy_checkpoint,
get_optim_scheduler,
)
from xautodl.utils import get_model_infos, obtain_accuracy
from xautodl.log_utils import AverageMeter, time_string, convert_secs2time
from xautodl.models import get_cell_based_tiny_net, get_search_spaces
from nas_201_api import NASBench201API as API
def _concat(xs):
return torch.cat([x.view(-1) for x in xs])
def _hessian_vector_product(
vector, network, criterion, base_inputs, base_targets, r=1e-2
):
R = r / _concat(vector).norm()
for p, v in zip(network.module.get_weights(), vector):
p.data.add_(R, v)
_, logits = network(base_inputs)
loss = criterion(logits, base_targets)
grads_p = torch.autograd.grad(loss, network.module.get_alphas())
for p, v in zip(network.module.get_weights(), vector):
p.data.sub_(2 * R, v)
_, logits = network(base_inputs)
loss = criterion(logits, base_targets)
grads_n = torch.autograd.grad(loss, network.module.get_alphas())
for p, v in zip(network.module.get_weights(), vector):
p.data.add_(R, v)
return [(x - y).div_(2 * R) for x, y in zip(grads_p, grads_n)]
def backward_step_unrolled(
network,
criterion,
base_inputs,
base_targets,
w_optimizer,
arch_inputs,
arch_targets,
):
# _compute_unrolled_model
_, logits = network(base_inputs)
loss = criterion(logits, base_targets)
LR, WD, momentum = (
w_optimizer.param_groups[0]["lr"],
w_optimizer.param_groups[0]["weight_decay"],
w_optimizer.param_groups[0]["momentum"],
)
with torch.no_grad():
theta = _concat(network.module.get_weights())
try:
moment = _concat(
w_optimizer.state[v]["momentum_buffer"]
for v in network.module.get_weights()
)
moment = moment.mul_(momentum)
except:
moment = torch.zeros_like(theta)
dtheta = (
_concat(torch.autograd.grad(loss, network.module.get_weights()))
+ WD * theta
)
params = theta.sub(LR, moment + dtheta)
unrolled_model = deepcopy(network)
model_dict = unrolled_model.state_dict()
new_params, offset = {}, 0
for k, v in network.named_parameters():
if "arch_parameters" in k:
continue
v_length = np.prod(v.size())
new_params[k] = params[offset : offset + v_length].view(v.size())
offset += v_length
model_dict.update(new_params)
unrolled_model.load_state_dict(model_dict)
unrolled_model.zero_grad()
_, unrolled_logits = unrolled_model(arch_inputs)
unrolled_loss = criterion(unrolled_logits, arch_targets)
unrolled_loss.backward()
dalpha = unrolled_model.module.arch_parameters.grad
vector = [v.grad.data for v in unrolled_model.module.get_weights()]
[implicit_grads] = _hessian_vector_product(
vector, network, criterion, base_inputs, base_targets
)
dalpha.data.sub_(LR, implicit_grads.data)
if network.module.arch_parameters.grad is None:
network.module.arch_parameters.grad = deepcopy(dalpha)
else:
network.module.arch_parameters.grad.data.copy_(dalpha.data)
return unrolled_loss.detach(), unrolled_logits.detach()
def search_func(
xloader,
network,
criterion,
scheduler,
w_optimizer,
a_optimizer,
epoch_str,
print_freq,
logger,
):
data_time, batch_time = AverageMeter(), AverageMeter()
base_losses, base_top1, base_top5 = AverageMeter(), AverageMeter(), AverageMeter()
arch_losses, arch_top1, arch_top5 = AverageMeter(), AverageMeter(), AverageMeter()
network.train()
end = time.time()
for step, (base_inputs, base_targets, arch_inputs, arch_targets) in enumerate(
xloader
):
scheduler.update(None, 1.0 * step / len(xloader))
base_targets = base_targets.cuda(non_blocking=True)
arch_targets = arch_targets.cuda(non_blocking=True)
# measure data loading time
data_time.update(time.time() - end)
# update the architecture-weight
a_optimizer.zero_grad()
arch_loss, arch_logits = backward_step_unrolled(
network,
criterion,
base_inputs,
base_targets,
w_optimizer,
arch_inputs,
arch_targets,
)
a_optimizer.step()
# record
arch_prec1, arch_prec5 = obtain_accuracy(
arch_logits.data, arch_targets.data, topk=(1, 5)
)
arch_losses.update(arch_loss.item(), arch_inputs.size(0))
arch_top1.update(arch_prec1.item(), arch_inputs.size(0))
arch_top5.update(arch_prec5.item(), arch_inputs.size(0))
# update the weights
w_optimizer.zero_grad()
_, logits = network(base_inputs)
base_loss = criterion(logits, base_targets)
base_loss.backward()
torch.nn.utils.clip_grad_norm_(network.parameters(), 5)
w_optimizer.step()
# record
base_prec1, base_prec5 = obtain_accuracy(
logits.data, base_targets.data, topk=(1, 5)
)
base_losses.update(base_loss.item(), base_inputs.size(0))
base_top1.update(base_prec1.item(), base_inputs.size(0))
base_top5.update(base_prec5.item(), base_inputs.size(0))
# measure elapsed time
batch_time.update(time.time() - end)
end = time.time()
if step % print_freq == 0 or step + 1 == len(xloader):
Sstr = (
"*SEARCH* "
+ time_string()
+ " [{:}][{:03d}/{:03d}]".format(epoch_str, step, len(xloader))
)
Tstr = "Time {batch_time.val:.2f} ({batch_time.avg:.2f}) Data {data_time.val:.2f} ({data_time.avg:.2f})".format(
batch_time=batch_time, data_time=data_time
)
Wstr = "Base [Loss {loss.val:.3f} ({loss.avg:.3f}) Prec@1 {top1.val:.2f} ({top1.avg:.2f}) Prec@5 {top5.val:.2f} ({top5.avg:.2f})]".format(
loss=base_losses, top1=base_top1, top5=base_top5
)
Astr = "Arch [Loss {loss.val:.3f} ({loss.avg:.3f}) Prec@1 {top1.val:.2f} ({top1.avg:.2f}) Prec@5 {top5.val:.2f} ({top5.avg:.2f})]".format(
loss=arch_losses, top1=arch_top1, top5=arch_top5
)
logger.log(Sstr + " " + Tstr + " " + Wstr + " " + Astr)
return base_losses.avg, base_top1.avg, base_top5.avg
def valid_func(xloader, network, criterion):
data_time, batch_time = AverageMeter(), AverageMeter()
arch_losses, arch_top1, arch_top5 = AverageMeter(), AverageMeter(), AverageMeter()
network.eval()
end = time.time()
with torch.no_grad():
for step, (arch_inputs, arch_targets) in enumerate(xloader):
arch_targets = arch_targets.cuda(non_blocking=True)
# measure data loading time
data_time.update(time.time() - end)
# prediction
_, logits = network(arch_inputs)
arch_loss = criterion(logits, arch_targets)
# record
arch_prec1, arch_prec5 = obtain_accuracy(
logits.data, arch_targets.data, topk=(1, 5)
)
arch_losses.update(arch_loss.item(), arch_inputs.size(0))
arch_top1.update(arch_prec1.item(), arch_inputs.size(0))
arch_top5.update(arch_prec5.item(), arch_inputs.size(0))
# measure elapsed time
batch_time.update(time.time() - end)
end = time.time()
return arch_losses.avg, arch_top1.avg, arch_top5.avg
def main(xargs):
assert torch.cuda.is_available(), "CUDA is not available."
torch.backends.cudnn.enabled = True
torch.backends.cudnn.benchmark = False
torch.backends.cudnn.deterministic = True
torch.set_num_threads(xargs.workers)
prepare_seed(xargs.rand_seed)
logger = prepare_logger(args)
train_data, valid_data, xshape, class_num = get_datasets(
xargs.dataset, xargs.data_path, -1
)
config = load_config(
xargs.config_path, {"class_num": class_num, "xshape": xshape}, logger
)
search_loader, _, valid_loader = get_nas_search_loaders(
train_data,
valid_data,
xargs.dataset,
"configs/nas-benchmark/",
config.batch_size,
xargs.workers,
)
logger.log(
"||||||| {:10s} ||||||| Search-Loader-Num={:}, Valid-Loader-Num={:}, batch size={:}".format(
xargs.dataset, len(search_loader), len(valid_loader), config.batch_size
)
)
logger.log("||||||| {:10s} ||||||| Config={:}".format(xargs.dataset, config))
search_space = get_search_spaces("cell", xargs.search_space_name)
model_config = dict2config(
{
"name": "DARTS-V2",
"C": xargs.channel,
"N": xargs.num_cells,
"max_nodes": xargs.max_nodes,
"num_classes": class_num,
"space": search_space,
"affine": False,
"track_running_stats": bool(xargs.track_running_stats),
},
None,
)
search_model = get_cell_based_tiny_net(model_config)
logger.log("search-model :\n{:}".format(search_model))
w_optimizer, w_scheduler, criterion = get_optim_scheduler(
search_model.get_weights(), config
)
a_optimizer = torch.optim.Adam(
search_model.get_alphas(),
lr=xargs.arch_learning_rate,
betas=(0.5, 0.999),
weight_decay=xargs.arch_weight_decay,
)
logger.log("w-optimizer : {:}".format(w_optimizer))
logger.log("a-optimizer : {:}".format(a_optimizer))
logger.log("w-scheduler : {:}".format(w_scheduler))
logger.log("criterion : {:}".format(criterion))
flop, param = get_model_infos(search_model, xshape)
# logger.log('{:}'.format(search_model))
logger.log("FLOP = {:.2f} M, Params = {:.2f} MB".format(flop, param))
if xargs.arch_nas_dataset is None:
api = None
else:
api = API(xargs.arch_nas_dataset)
logger.log("{:} create API = {:} done".format(time_string(), api))
last_info, model_base_path, model_best_path = (
logger.path("info"),
logger.path("model"),
logger.path("best"),
)
network, criterion = torch.nn.DataParallel(search_model).cuda(), criterion.cuda()
if last_info.exists(): # automatically resume from previous checkpoint
logger.log(
"=> loading checkpoint of the last-info '{:}' start".format(last_info)
)
last_info = torch.load(last_info)
start_epoch = last_info["epoch"]
checkpoint = torch.load(last_info["last_checkpoint"])
genotypes = checkpoint["genotypes"]
valid_accuracies = checkpoint["valid_accuracies"]
search_model.load_state_dict(checkpoint["search_model"])
w_scheduler.load_state_dict(checkpoint["w_scheduler"])
w_optimizer.load_state_dict(checkpoint["w_optimizer"])
a_optimizer.load_state_dict(checkpoint["a_optimizer"])
logger.log(
"=> loading checkpoint of the last-info '{:}' start with {:}-th epoch.".format(
last_info, start_epoch
)
)
else:
logger.log("=> do not find the last-info file : {:}".format(last_info))
start_epoch, valid_accuracies, genotypes = (
0,
{"best": -1},
{-1: search_model.genotype()},
)
# start training
start_time, search_time, epoch_time, total_epoch = (
time.time(),
AverageMeter(),
AverageMeter(),
config.epochs + config.warmup,
)
for epoch in range(start_epoch, total_epoch):
w_scheduler.update(epoch, 0.0)
need_time = "Time Left: {:}".format(
convert_secs2time(epoch_time.val * (total_epoch - epoch), True)
)
epoch_str = "{:03d}-{:03d}".format(epoch, total_epoch)
min_LR = min(w_scheduler.get_lr())
logger.log(
"\n[Search the {:}-th epoch] {:}, LR={:}".format(
epoch_str, need_time, min_LR
)
)
search_w_loss, search_w_top1, search_w_top5 = search_func(
search_loader,
network,
criterion,
w_scheduler,
w_optimizer,
a_optimizer,
epoch_str,
xargs.print_freq,
logger,
)
search_time.update(time.time() - start_time)
logger.log(
"[{:}] searching : loss={:.2f}, accuracy@1={:.2f}%, accuracy@5={:.2f}%, time-cost={:.1f} s".format(
epoch_str, search_w_loss, search_w_top1, search_w_top5, search_time.sum
)
)
valid_a_loss, valid_a_top1, valid_a_top5 = valid_func(
valid_loader, network, criterion
)
logger.log(
"[{:}] evaluate : loss={:.2f}, accuracy@1={:.2f}%, accuracy@5={:.2f}%".format(
epoch_str, valid_a_loss, valid_a_top1, valid_a_top5
)
)
# check the best accuracy
valid_accuracies[epoch] = valid_a_top1
if valid_a_top1 > valid_accuracies["best"]:
valid_accuracies["best"] = valid_a_top1
genotypes["best"] = search_model.genotype()
find_best = True
else:
find_best = False
genotypes[epoch] = search_model.genotype()
logger.log(
"<<<--->>> The {:}-th epoch : {:}".format(epoch_str, genotypes[epoch])
)
# save checkpoint
save_path = save_checkpoint(
{
"epoch": epoch + 1,
"args": deepcopy(xargs),
"search_model": search_model.state_dict(),
"w_optimizer": w_optimizer.state_dict(),
"a_optimizer": a_optimizer.state_dict(),
"w_scheduler": w_scheduler.state_dict(),
"genotypes": genotypes,
"valid_accuracies": valid_accuracies,
},
model_base_path,
logger,
)
last_info = save_checkpoint(
{
"epoch": epoch + 1,
"args": deepcopy(args),
"last_checkpoint": save_path,
},
logger.path("info"),
logger,
)
if find_best:
logger.log(
"<<<--->>> The {:}-th epoch : find the highest validation accuracy : {:.2f}%.".format(
epoch_str, valid_a_top1
)
)
copy_checkpoint(model_base_path, model_best_path, logger)
with torch.no_grad():
logger.log(
"arch-parameters :\n{:}".format(
nn.functional.softmax(search_model.arch_parameters, dim=-1).cpu()
)
)
if api is not None:
logger.log("{:}".format(api.query_by_arch(genotypes[epoch], "200")))
# measure elapsed time
epoch_time.update(time.time() - start_time)
start_time = time.time()
logger.log("\n" + "-" * 100)
# check the performance from the architecture dataset
logger.log(
"DARTS-V2 : run {:} epochs, cost {:.1f} s, last-geno is {:}.".format(
total_epoch, search_time.sum, genotypes[total_epoch - 1]
)
)
if api is not None:
logger.log("{:}".format(api.query_by_arch(genotypes[total_epoch - 1], "200")))
logger.close()
if __name__ == "__main__":
parser = argparse.ArgumentParser("DARTS Second Order")
parser.add_argument("--data_path", type=str, help="The path to dataset")
parser.add_argument(
"--dataset",
type=str,
choices=["cifar10", "cifar100", "ImageNet16-120"],
help="Choose between Cifar10/100 and ImageNet-16.",
)
# channels and number-of-cells
parser.add_argument("--config_path", type=str, help="The config path.")
parser.add_argument("--search_space_name", type=str, help="The search space name.")
parser.add_argument("--max_nodes", type=int, help="The maximum number of nodes.")
parser.add_argument("--channel", type=int, help="The number of channels.")
parser.add_argument(
"--num_cells", type=int, help="The number of cells in one stage."
)
parser.add_argument(
"--track_running_stats",
type=int,
choices=[0, 1],
help="Whether use track_running_stats or not in the BN layer.",
)
# architecture leraning rate
parser.add_argument(
"--arch_learning_rate",
type=float,
default=3e-4,
help="learning rate for arch encoding",
)
parser.add_argument(
"--arch_weight_decay",
type=float,
default=1e-3,
help="weight decay for arch encoding",
)
# log
parser.add_argument(
"--workers",
type=int,
default=2,
help="number of data loading workers (default: 2)",
)
parser.add_argument(
"--save_dir", type=str, help="Folder to save checkpoints and log."
)
parser.add_argument(
"--arch_nas_dataset",
type=str,
help="The path to load the architecture dataset (tiny-nas-benchmark).",
)
parser.add_argument("--print_freq", type=int, help="print frequency (default: 200)")
parser.add_argument("--rand_seed", type=int, help="manual seed")
args = parser.parse_args()
if args.rand_seed is None or args.rand_seed < 0:
args.rand_seed = random.randint(1, 100000)
main(args)