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Upload apex-master/examples/imagenet/main_amp.py with huggingface_hub

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apex-master/examples/imagenet/main_amp.py ADDED
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1
+ import argparse
2
+ import os
3
+ import shutil
4
+ import time
5
+
6
+ import torch
7
+ import torch.nn as nn
8
+ import torch.nn.parallel
9
+ import torch.backends.cudnn as cudnn
10
+ import torch.distributed as dist
11
+ import torch.optim
12
+ import torch.utils.data
13
+ import torch.utils.data.distributed
14
+ import torchvision.transforms as transforms
15
+ import torchvision.datasets as datasets
16
+ import torchvision.models as models
17
+
18
+ import numpy as np
19
+
20
+ try:
21
+ from apex.parallel import DistributedDataParallel as DDP
22
+ from apex.fp16_utils import *
23
+ from apex import amp, optimizers
24
+ from apex.multi_tensor_apply import multi_tensor_applier
25
+ except ImportError:
26
+ raise ImportError("Please install apex from https://www.github.com/nvidia/apex to run this example.")
27
+
28
+ def fast_collate(batch, memory_format):
29
+
30
+ imgs = [img[0] for img in batch]
31
+ targets = torch.tensor([target[1] for target in batch], dtype=torch.int64)
32
+ w = imgs[0].size[0]
33
+ h = imgs[0].size[1]
34
+ tensor = torch.zeros( (len(imgs), 3, h, w), dtype=torch.uint8).contiguous(memory_format=memory_format)
35
+ for i, img in enumerate(imgs):
36
+ nump_array = np.asarray(img, dtype=np.uint8)
37
+ if(nump_array.ndim < 3):
38
+ nump_array = np.expand_dims(nump_array, axis=-1)
39
+ nump_array = np.rollaxis(nump_array, 2)
40
+ tensor[i] += torch.from_numpy(nump_array)
41
+ return tensor, targets
42
+
43
+
44
+ def parse():
45
+ model_names = sorted(name for name in models.__dict__
46
+ if name.islower() and not name.startswith("__")
47
+ and callable(models.__dict__[name]))
48
+
49
+ parser = argparse.ArgumentParser(description='PyTorch ImageNet Training')
50
+ parser.add_argument('data', metavar='DIR',
51
+ help='path to dataset')
52
+ parser.add_argument('--arch', '-a', metavar='ARCH', default='resnet18',
53
+ choices=model_names,
54
+ help='model architecture: ' +
55
+ ' | '.join(model_names) +
56
+ ' (default: resnet18)')
57
+ parser.add_argument('-j', '--workers', default=4, type=int, metavar='N',
58
+ help='number of data loading workers (default: 4)')
59
+ parser.add_argument('--epochs', default=90, type=int, metavar='N',
60
+ help='number of total epochs to run')
61
+ parser.add_argument('--start-epoch', default=0, type=int, metavar='N',
62
+ help='manual epoch number (useful on restarts)')
63
+ parser.add_argument('-b', '--batch-size', default=256, type=int,
64
+ metavar='N', help='mini-batch size per process (default: 256)')
65
+ parser.add_argument('--lr', '--learning-rate', default=0.1, type=float,
66
+ metavar='LR', help='Initial learning rate. Will be scaled by <global batch size>/256: args.lr = args.lr*float(args.batch_size*args.world_size)/256. A warmup schedule will also be applied over the first 5 epochs.')
67
+ parser.add_argument('--momentum', default=0.9, type=float, metavar='M',
68
+ help='momentum')
69
+ parser.add_argument('--weight-decay', '--wd', default=1e-4, type=float,
70
+ metavar='W', help='weight decay (default: 1e-4)')
71
+ parser.add_argument('--print-freq', '-p', default=10, type=int,
72
+ metavar='N', help='print frequency (default: 10)')
73
+ parser.add_argument('--resume', default='', type=str, metavar='PATH',
74
+ help='path to latest checkpoint (default: none)')
75
+ parser.add_argument('-e', '--evaluate', dest='evaluate', action='store_true',
76
+ help='evaluate model on validation set')
77
+ parser.add_argument('--pretrained', dest='pretrained', action='store_true',
78
+ help='use pre-trained model')
79
+
80
+ parser.add_argument('--prof', default=-1, type=int,
81
+ help='Only run 10 iterations for profiling.')
82
+ parser.add_argument('--deterministic', action='store_true')
83
+
84
+ parser.add_argument("--local_rank", default=os.getenv('LOCAL_RANK', 0), type=int)
85
+ parser.add_argument('--sync_bn', action='store_true',
86
+ help='enabling apex sync BN.')
87
+
88
+ parser.add_argument('--opt-level', type=str)
89
+ parser.add_argument('--keep-batchnorm-fp32', type=str, default=None)
90
+ parser.add_argument('--loss-scale', type=str, default=None)
91
+ parser.add_argument('--channels-last', type=bool, default=False)
92
+ args = parser.parse_args()
93
+ return args
94
+
95
+ def main():
96
+ global best_prec1, args
97
+
98
+ args = parse()
99
+ print("opt_level = {}".format(args.opt_level))
100
+ print("keep_batchnorm_fp32 = {}".format(args.keep_batchnorm_fp32), type(args.keep_batchnorm_fp32))
101
+ print("loss_scale = {}".format(args.loss_scale), type(args.loss_scale))
102
+
103
+ print("\nCUDNN VERSION: {}\n".format(torch.backends.cudnn.version()))
104
+
105
+ cudnn.benchmark = True
106
+ best_prec1 = 0
107
+ if args.deterministic:
108
+ cudnn.benchmark = False
109
+ cudnn.deterministic = True
110
+ torch.manual_seed(args.local_rank)
111
+ torch.set_printoptions(precision=10)
112
+
113
+ args.distributed = False
114
+ if 'WORLD_SIZE' in os.environ:
115
+ args.distributed = int(os.environ['WORLD_SIZE']) > 1
116
+
117
+ args.gpu = 0
118
+ args.world_size = 1
119
+
120
+ if args.distributed:
121
+ args.gpu = args.local_rank
122
+ torch.cuda.set_device(args.gpu)
123
+ torch.distributed.init_process_group(backend='nccl',
124
+ init_method='env://')
125
+ args.world_size = torch.distributed.get_world_size()
126
+
127
+ assert torch.backends.cudnn.enabled, "Amp requires cudnn backend to be enabled."
128
+
129
+ if args.channels_last:
130
+ memory_format = torch.channels_last
131
+ else:
132
+ memory_format = torch.contiguous_format
133
+
134
+ # create model
135
+ if args.pretrained:
136
+ print("=> using pre-trained model '{}'".format(args.arch))
137
+ model = models.__dict__[args.arch](pretrained=True)
138
+ else:
139
+ print("=> creating model '{}'".format(args.arch))
140
+ model = models.__dict__[args.arch]()
141
+
142
+ if args.sync_bn:
143
+ import apex
144
+ print("using apex synced BN")
145
+ model = apex.parallel.convert_syncbn_model(model)
146
+
147
+ model = model.cuda().to(memory_format=memory_format)
148
+
149
+ # Scale learning rate based on global batch size
150
+ args.lr = args.lr*float(args.batch_size*args.world_size)/256.
151
+ optimizer = torch.optim.SGD(model.parameters(), args.lr,
152
+ momentum=args.momentum,
153
+ weight_decay=args.weight_decay)
154
+
155
+ # Initialize Amp. Amp accepts either values or strings for the optional override arguments,
156
+ # for convenient interoperation with argparse.
157
+ model, optimizer = amp.initialize(model, optimizer,
158
+ opt_level=args.opt_level,
159
+ keep_batchnorm_fp32=args.keep_batchnorm_fp32,
160
+ loss_scale=args.loss_scale
161
+ )
162
+
163
+ # For distributed training, wrap the model with apex.parallel.DistributedDataParallel.
164
+ # This must be done AFTER the call to amp.initialize. If model = DDP(model) is called
165
+ # before model, ... = amp.initialize(model, ...), the call to amp.initialize may alter
166
+ # the types of model's parameters in a way that disrupts or destroys DDP's allreduce hooks.
167
+ if args.distributed:
168
+ # By default, apex.parallel.DistributedDataParallel overlaps communication with
169
+ # computation in the backward pass.
170
+ # model = DDP(model)
171
+ # delay_allreduce delays all communication to the end of the backward pass.
172
+ model = DDP(model, delay_allreduce=True)
173
+
174
+ # define loss function (criterion) and optimizer
175
+ criterion = nn.CrossEntropyLoss().cuda()
176
+
177
+ # Optionally resume from a checkpoint
178
+ if args.resume:
179
+ # Use a local scope to avoid dangling references
180
+ def resume():
181
+ if os.path.isfile(args.resume):
182
+ print("=> loading checkpoint '{}'".format(args.resume))
183
+ checkpoint = torch.load(args.resume, map_location = lambda storage, loc: storage.cuda(args.gpu))
184
+ args.start_epoch = checkpoint['epoch']
185
+ global best_prec1
186
+ best_prec1 = checkpoint['best_prec1']
187
+ model.load_state_dict(checkpoint['state_dict'])
188
+ optimizer.load_state_dict(checkpoint['optimizer'])
189
+ print("=> loaded checkpoint '{}' (epoch {})"
190
+ .format(args.resume, checkpoint['epoch']))
191
+ else:
192
+ print("=> no checkpoint found at '{}'".format(args.resume))
193
+ resume()
194
+
195
+ # Data loading code
196
+ traindir = os.path.join(args.data, 'train')
197
+ valdir = os.path.join(args.data, 'val')
198
+
199
+ if(args.arch == "inception_v3"):
200
+ raise RuntimeError("Currently, inception_v3 is not supported by this example.")
201
+ # crop_size = 299
202
+ # val_size = 320 # I chose this value arbitrarily, we can adjust.
203
+ else:
204
+ crop_size = 224
205
+ val_size = 256
206
+
207
+ train_dataset = datasets.ImageFolder(
208
+ traindir,
209
+ transforms.Compose([
210
+ transforms.RandomResizedCrop(crop_size),
211
+ transforms.RandomHorizontalFlip(),
212
+ # transforms.ToTensor(), Too slow
213
+ # normalize,
214
+ ]))
215
+ val_dataset = datasets.ImageFolder(valdir, transforms.Compose([
216
+ transforms.Resize(val_size),
217
+ transforms.CenterCrop(crop_size),
218
+ ]))
219
+
220
+ train_sampler = None
221
+ val_sampler = None
222
+ if args.distributed:
223
+ train_sampler = torch.utils.data.distributed.DistributedSampler(train_dataset)
224
+ val_sampler = torch.utils.data.distributed.DistributedSampler(val_dataset)
225
+
226
+ collate_fn = lambda b: fast_collate(b, memory_format)
227
+
228
+ train_loader = torch.utils.data.DataLoader(
229
+ train_dataset, batch_size=args.batch_size, shuffle=(train_sampler is None),
230
+ num_workers=args.workers, pin_memory=True, sampler=train_sampler, collate_fn=collate_fn)
231
+
232
+ val_loader = torch.utils.data.DataLoader(
233
+ val_dataset,
234
+ batch_size=args.batch_size, shuffle=False,
235
+ num_workers=args.workers, pin_memory=True,
236
+ sampler=val_sampler,
237
+ collate_fn=collate_fn)
238
+
239
+ if args.evaluate:
240
+ validate(val_loader, model, criterion)
241
+ return
242
+
243
+ for epoch in range(args.start_epoch, args.epochs):
244
+ if args.distributed:
245
+ train_sampler.set_epoch(epoch)
246
+
247
+ # train for one epoch
248
+ train(train_loader, model, criterion, optimizer, epoch)
249
+
250
+ # evaluate on validation set
251
+ prec1 = validate(val_loader, model, criterion)
252
+
253
+ # remember best prec@1 and save checkpoint
254
+ if args.local_rank == 0:
255
+ is_best = prec1 > best_prec1
256
+ best_prec1 = max(prec1, best_prec1)
257
+ save_checkpoint({
258
+ 'epoch': epoch + 1,
259
+ 'arch': args.arch,
260
+ 'state_dict': model.state_dict(),
261
+ 'best_prec1': best_prec1,
262
+ 'optimizer' : optimizer.state_dict(),
263
+ }, is_best)
264
+
265
+ class data_prefetcher():
266
+ def __init__(self, loader):
267
+ self.loader = iter(loader)
268
+ self.stream = torch.cuda.Stream()
269
+ self.mean = torch.tensor([0.485 * 255, 0.456 * 255, 0.406 * 255]).cuda().view(1,3,1,1)
270
+ self.std = torch.tensor([0.229 * 255, 0.224 * 255, 0.225 * 255]).cuda().view(1,3,1,1)
271
+ # With Amp, it isn't necessary to manually convert data to half.
272
+ # if args.fp16:
273
+ # self.mean = self.mean.half()
274
+ # self.std = self.std.half()
275
+ self.preload()
276
+
277
+ def preload(self):
278
+ try:
279
+ self.next_input, self.next_target = next(self.loader)
280
+ except StopIteration:
281
+ self.next_input = None
282
+ self.next_target = None
283
+ return
284
+ # if record_stream() doesn't work, another option is to make sure device inputs are created
285
+ # on the main stream.
286
+ # self.next_input_gpu = torch.empty_like(self.next_input, device='cuda')
287
+ # self.next_target_gpu = torch.empty_like(self.next_target, device='cuda')
288
+ # Need to make sure the memory allocated for next_* is not still in use by the main stream
289
+ # at the time we start copying to next_*:
290
+ # self.stream.wait_stream(torch.cuda.current_stream())
291
+ with torch.cuda.stream(self.stream):
292
+ self.next_input = self.next_input.cuda(non_blocking=True)
293
+ self.next_target = self.next_target.cuda(non_blocking=True)
294
+ # more code for the alternative if record_stream() doesn't work:
295
+ # copy_ will record the use of the pinned source tensor in this side stream.
296
+ # self.next_input_gpu.copy_(self.next_input, non_blocking=True)
297
+ # self.next_target_gpu.copy_(self.next_target, non_blocking=True)
298
+ # self.next_input = self.next_input_gpu
299
+ # self.next_target = self.next_target_gpu
300
+
301
+ # With Amp, it isn't necessary to manually convert data to half.
302
+ # if args.fp16:
303
+ # self.next_input = self.next_input.half()
304
+ # else:
305
+ self.next_input = self.next_input.float()
306
+ self.next_input = self.next_input.sub_(self.mean).div_(self.std)
307
+
308
+ def next(self):
309
+ torch.cuda.current_stream().wait_stream(self.stream)
310
+ input = self.next_input
311
+ target = self.next_target
312
+ if input is not None:
313
+ input.record_stream(torch.cuda.current_stream())
314
+ if target is not None:
315
+ target.record_stream(torch.cuda.current_stream())
316
+ self.preload()
317
+ return input, target
318
+
319
+
320
+ def train(train_loader, model, criterion, optimizer, epoch):
321
+ batch_time = AverageMeter()
322
+ losses = AverageMeter()
323
+ top1 = AverageMeter()
324
+ top5 = AverageMeter()
325
+
326
+ # switch to train mode
327
+ model.train()
328
+ end = time.time()
329
+
330
+ prefetcher = data_prefetcher(train_loader)
331
+ input, target = prefetcher.next()
332
+ i = 0
333
+ while input is not None:
334
+ i += 1
335
+ if args.prof >= 0 and i == args.prof:
336
+ print("Profiling begun at iteration {}".format(i))
337
+ torch.cuda.cudart().cudaProfilerStart()
338
+
339
+ if args.prof >= 0: torch.cuda.nvtx.range_push("Body of iteration {}".format(i))
340
+
341
+ adjust_learning_rate(optimizer, epoch, i, len(train_loader))
342
+
343
+ # compute output
344
+ if args.prof >= 0: torch.cuda.nvtx.range_push("forward")
345
+ output = model(input)
346
+ if args.prof >= 0: torch.cuda.nvtx.range_pop()
347
+ loss = criterion(output, target)
348
+
349
+ # compute gradient and do SGD step
350
+ optimizer.zero_grad()
351
+
352
+ if args.prof >= 0: torch.cuda.nvtx.range_push("backward")
353
+ with amp.scale_loss(loss, optimizer) as scaled_loss:
354
+ scaled_loss.backward()
355
+ if args.prof >= 0: torch.cuda.nvtx.range_pop()
356
+
357
+ # for param in model.parameters():
358
+ # print(param.data.double().sum().item(), param.grad.data.double().sum().item())
359
+
360
+ if args.prof >= 0: torch.cuda.nvtx.range_push("optimizer.step()")
361
+ optimizer.step()
362
+ if args.prof >= 0: torch.cuda.nvtx.range_pop()
363
+
364
+ if i%args.print_freq == 0:
365
+ # Every print_freq iterations, check the loss, accuracy, and speed.
366
+ # For best performance, it doesn't make sense to print these metrics every
367
+ # iteration, since they incur an allreduce and some host<->device syncs.
368
+
369
+ # Measure accuracy
370
+ prec1, prec5 = accuracy(output.data, target, topk=(1, 5))
371
+
372
+ # Average loss and accuracy across processes for logging
373
+ if args.distributed:
374
+ reduced_loss = reduce_tensor(loss.data)
375
+ prec1 = reduce_tensor(prec1)
376
+ prec5 = reduce_tensor(prec5)
377
+ else:
378
+ reduced_loss = loss.data
379
+
380
+ # to_python_float incurs a host<->device sync
381
+ losses.update(to_python_float(reduced_loss), input.size(0))
382
+ top1.update(to_python_float(prec1), input.size(0))
383
+ top5.update(to_python_float(prec5), input.size(0))
384
+
385
+ torch.cuda.synchronize()
386
+ batch_time.update((time.time() - end)/args.print_freq)
387
+ end = time.time()
388
+
389
+ if args.local_rank == 0:
390
+ print('Epoch: [{0}][{1}/{2}]\t'
391
+ 'Time {batch_time.val:.3f} ({batch_time.avg:.3f})\t'
392
+ 'Speed {3:.3f} ({4:.3f})\t'
393
+ 'Loss {loss.val:.10f} ({loss.avg:.4f})\t'
394
+ 'Prec@1 {top1.val:.3f} ({top1.avg:.3f})\t'
395
+ 'Prec@5 {top5.val:.3f} ({top5.avg:.3f})'.format(
396
+ epoch, i, len(train_loader),
397
+ args.world_size*args.batch_size/batch_time.val,
398
+ args.world_size*args.batch_size/batch_time.avg,
399
+ batch_time=batch_time,
400
+ loss=losses, top1=top1, top5=top5))
401
+ if args.prof >= 0: torch.cuda.nvtx.range_push("prefetcher.next()")
402
+ input, target = prefetcher.next()
403
+ if args.prof >= 0: torch.cuda.nvtx.range_pop()
404
+
405
+ # Pop range "Body of iteration {}".format(i)
406
+ if args.prof >= 0: torch.cuda.nvtx.range_pop()
407
+
408
+ if args.prof >= 0 and i == args.prof + 10:
409
+ print("Profiling ended at iteration {}".format(i))
410
+ torch.cuda.cudart().cudaProfilerStop()
411
+ quit()
412
+
413
+
414
+ def validate(val_loader, model, criterion):
415
+ batch_time = AverageMeter()
416
+ losses = AverageMeter()
417
+ top1 = AverageMeter()
418
+ top5 = AverageMeter()
419
+
420
+ # switch to evaluate mode
421
+ model.eval()
422
+
423
+ end = time.time()
424
+
425
+ prefetcher = data_prefetcher(val_loader)
426
+ input, target = prefetcher.next()
427
+ i = 0
428
+ while input is not None:
429
+ i += 1
430
+
431
+ # compute output
432
+ with torch.no_grad():
433
+ output = model(input)
434
+ loss = criterion(output, target)
435
+
436
+ # measure accuracy and record loss
437
+ prec1, prec5 = accuracy(output.data, target, topk=(1, 5))
438
+
439
+ if args.distributed:
440
+ reduced_loss = reduce_tensor(loss.data)
441
+ prec1 = reduce_tensor(prec1)
442
+ prec5 = reduce_tensor(prec5)
443
+ else:
444
+ reduced_loss = loss.data
445
+
446
+ losses.update(to_python_float(reduced_loss), input.size(0))
447
+ top1.update(to_python_float(prec1), input.size(0))
448
+ top5.update(to_python_float(prec5), input.size(0))
449
+
450
+ # measure elapsed time
451
+ batch_time.update(time.time() - end)
452
+ end = time.time()
453
+
454
+ # TODO: Change timings to mirror train().
455
+ if args.local_rank == 0 and i % args.print_freq == 0:
456
+ print('Test: [{0}/{1}]\t'
457
+ 'Time {batch_time.val:.3f} ({batch_time.avg:.3f})\t'
458
+ 'Speed {2:.3f} ({3:.3f})\t'
459
+ 'Loss {loss.val:.4f} ({loss.avg:.4f})\t'
460
+ 'Prec@1 {top1.val:.3f} ({top1.avg:.3f})\t'
461
+ 'Prec@5 {top5.val:.3f} ({top5.avg:.3f})'.format(
462
+ i, len(val_loader),
463
+ args.world_size * args.batch_size / batch_time.val,
464
+ args.world_size * args.batch_size / batch_time.avg,
465
+ batch_time=batch_time, loss=losses,
466
+ top1=top1, top5=top5))
467
+
468
+ input, target = prefetcher.next()
469
+
470
+ print(' * Prec@1 {top1.avg:.3f} Prec@5 {top5.avg:.3f}'
471
+ .format(top1=top1, top5=top5))
472
+
473
+ return top1.avg
474
+
475
+
476
+ def save_checkpoint(state, is_best, filename='checkpoint.pth.tar'):
477
+ torch.save(state, filename)
478
+ if is_best:
479
+ shutil.copyfile(filename, 'model_best.pth.tar')
480
+
481
+
482
+ class AverageMeter(object):
483
+ """Computes and stores the average and current value"""
484
+ def __init__(self):
485
+ self.reset()
486
+
487
+ def reset(self):
488
+ self.val = 0
489
+ self.avg = 0
490
+ self.sum = 0
491
+ self.count = 0
492
+
493
+ def update(self, val, n=1):
494
+ self.val = val
495
+ self.sum += val * n
496
+ self.count += n
497
+ self.avg = self.sum / self.count
498
+
499
+
500
+ def adjust_learning_rate(optimizer, epoch, step, len_epoch):
501
+ """LR schedule that should yield 76% converged accuracy with batch size 256"""
502
+ factor = epoch // 30
503
+
504
+ if epoch >= 80:
505
+ factor = factor + 1
506
+
507
+ lr = args.lr*(0.1**factor)
508
+
509
+ """Warmup"""
510
+ if epoch < 5:
511
+ lr = lr*float(1 + step + epoch*len_epoch)/(5.*len_epoch)
512
+
513
+ # if(args.local_rank == 0):
514
+ # print("epoch = {}, step = {}, lr = {}".format(epoch, step, lr))
515
+
516
+ for param_group in optimizer.param_groups:
517
+ param_group['lr'] = lr
518
+
519
+
520
+ def accuracy(output, target, topk=(1,)):
521
+ """Computes the precision@k for the specified values of k"""
522
+ maxk = max(topk)
523
+ batch_size = target.size(0)
524
+
525
+ _, pred = output.topk(maxk, 1, True, True)
526
+ pred = pred.t()
527
+ correct = pred.eq(target.view(1, -1).expand_as(pred))
528
+
529
+ res = []
530
+ for k in topk:
531
+ correct_k = correct[:k].reshape(-1).float().sum(0, keepdim=True)
532
+ res.append(correct_k.mul_(100.0 / batch_size))
533
+ return res
534
+
535
+
536
+ def reduce_tensor(tensor):
537
+ rt = tensor.clone()
538
+ dist.all_reduce(rt, op=dist.reduce_op.SUM)
539
+ rt /= args.world_size
540
+ return rt
541
+
542
+ if __name__ == '__main__':
543
+ main()