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Upload apex-master/tests/L1/common/main_amp.py with huggingface_hub

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apex-master/tests/L1/common/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
+ model_names = sorted(name for name in models.__dict__
29
+ if name.islower() and not name.startswith("__")
30
+ and callable(models.__dict__[name]))
31
+
32
+ parser = argparse.ArgumentParser(description='PyTorch ImageNet Training')
33
+ parser.add_argument('data', metavar='DIR',
34
+ help='path to dataset')
35
+ parser.add_argument('--arch', '-a', metavar='ARCH', default='resnet18',
36
+ choices=model_names,
37
+ help='model architecture: ' +
38
+ ' | '.join(model_names) +
39
+ ' (default: resnet18)')
40
+ parser.add_argument('-j', '--workers', default=4, type=int, metavar='N',
41
+ help='number of data loading workers (default: 4)')
42
+ parser.add_argument('--epochs', default=90, type=int, metavar='N',
43
+ help='number of total epochs to run')
44
+ parser.add_argument('--start-epoch', default=0, type=int, metavar='N',
45
+ help='manual epoch number (useful on restarts)')
46
+ parser.add_argument('-b', '--batch-size', default=256, type=int,
47
+ metavar='N', help='mini-batch size per process (default: 256)')
48
+ parser.add_argument('--lr', '--learning-rate', default=0.1, type=float,
49
+ 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.')
50
+ parser.add_argument('--momentum', default=0.9, type=float, metavar='M',
51
+ help='momentum')
52
+ parser.add_argument('--weight-decay', '--wd', default=1e-4, type=float,
53
+ metavar='W', help='weight decay (default: 1e-4)')
54
+ parser.add_argument('--print-freq', '-p', default=10, type=int,
55
+ metavar='N', help='print frequency (default: 10)')
56
+ parser.add_argument('--resume', default='', type=str, metavar='PATH',
57
+ help='path to latest checkpoint (default: none)')
58
+ parser.add_argument('-e', '--evaluate', dest='evaluate', action='store_true',
59
+ help='evaluate model on validation set')
60
+ parser.add_argument('--pretrained', dest='pretrained', action='store_true',
61
+ help='use pre-trained model')
62
+
63
+ parser.add_argument('--prof', dest='prof', action='store_true',
64
+ help='Only run 10 iterations for profiling.')
65
+ parser.add_argument('--deterministic', action='store_true')
66
+
67
+ parser.add_argument("--local_rank", default=0, type=int)
68
+ parser.add_argument('--sync_bn', action='store_true',
69
+ help='enabling apex sync BN.')
70
+
71
+ parser.add_argument('--has-ext', action='store_true')
72
+ parser.add_argument('--opt-level', type=str)
73
+ parser.add_argument('--keep-batchnorm-fp32', type=str, default=None)
74
+ parser.add_argument('--loss-scale', type=str, default=None)
75
+ parser.add_argument('--fused-adam', action='store_true')
76
+
77
+ parser.add_argument('--prints-to-process', type=int, default=10)
78
+
79
+ cudnn.benchmark = True
80
+
81
+ def fast_collate(batch):
82
+ imgs = [img[0] for img in batch]
83
+ targets = torch.tensor([target[1] for target in batch], dtype=torch.int64)
84
+ w = imgs[0].size[0]
85
+ h = imgs[0].size[1]
86
+ tensor = torch.zeros( (len(imgs), 3, h, w), dtype=torch.uint8 )
87
+ for i, img in enumerate(imgs):
88
+ nump_array = np.asarray(img, dtype=np.uint8)
89
+ if(nump_array.ndim < 3):
90
+ nump_array = np.expand_dims(nump_array, axis=-1)
91
+ nump_array = np.rollaxis(nump_array, 2)
92
+
93
+ tensor[i] += torch.from_numpy(nump_array)
94
+
95
+ return tensor, targets
96
+
97
+ best_prec1 = 0
98
+ args = parser.parse_args()
99
+
100
+ # Let multi_tensor_applier be the canary in the coalmine
101
+ # that verifies if the backend is what we think it is
102
+ assert multi_tensor_applier.available == args.has_ext
103
+
104
+ print("opt_level = {}".format(args.opt_level))
105
+ print("keep_batchnorm_fp32 = {}".format(args.keep_batchnorm_fp32), type(args.keep_batchnorm_fp32))
106
+ print("loss_scale = {}".format(args.loss_scale), type(args.loss_scale))
107
+
108
+
109
+ print("\nCUDNN VERSION: {}\n".format(torch.backends.cudnn.version()))
110
+
111
+ if args.deterministic:
112
+ cudnn.benchmark = False
113
+ cudnn.deterministic = True
114
+ torch.manual_seed(args.local_rank)
115
+ torch.set_printoptions(precision=10)
116
+
117
+ def main():
118
+ global best_prec1, args
119
+
120
+ args.distributed = False
121
+ if 'WORLD_SIZE' in os.environ:
122
+ args.distributed = int(os.environ['WORLD_SIZE']) > 1
123
+
124
+ args.gpu = 0
125
+ args.world_size = 1
126
+
127
+ if args.distributed:
128
+ args.gpu = args.local_rank % torch.cuda.device_count()
129
+ torch.cuda.set_device(args.gpu)
130
+ torch.distributed.init_process_group(backend='nccl',
131
+ init_method='env://')
132
+ args.world_size = torch.distributed.get_world_size()
133
+
134
+ assert torch.backends.cudnn.enabled, "Amp requires cudnn backend to be enabled."
135
+
136
+ # create model
137
+ if args.pretrained:
138
+ print("=> using pre-trained model '{}'".format(args.arch))
139
+ model = models.__dict__[args.arch](pretrained=True)
140
+ else:
141
+ print("=> creating model '{}'".format(args.arch))
142
+ model = models.__dict__[args.arch]()
143
+
144
+ if args.sync_bn:
145
+ import apex
146
+ print("using apex synced BN")
147
+ model = apex.parallel.convert_syncbn_model(model)
148
+
149
+ model = model.cuda()
150
+
151
+ # Scale learning rate based on global batch size
152
+ args.lr = args.lr*float(args.batch_size*args.world_size)/256.
153
+ if args.fused_adam:
154
+ optimizer = optimizers.FusedAdam(model.parameters())
155
+ else:
156
+ optimizer = torch.optim.SGD(model.parameters(), args.lr,
157
+ momentum=args.momentum,
158
+ weight_decay=args.weight_decay)
159
+
160
+ model, optimizer = amp.initialize(
161
+ model, optimizer,
162
+ # enabled=False,
163
+ opt_level=args.opt_level,
164
+ keep_batchnorm_fp32=args.keep_batchnorm_fp32,
165
+ loss_scale=args.loss_scale
166
+ )
167
+
168
+ if args.distributed:
169
+ # By default, apex.parallel.DistributedDataParallel overlaps communication with
170
+ # computation in the backward pass.
171
+ # model = DDP(model)
172
+ # delay_allreduce delays all communication to the end of the backward pass.
173
+ model = DDP(model, delay_allreduce=True)
174
+
175
+ # define loss function (criterion) and optimizer
176
+ criterion = nn.CrossEntropyLoss().cuda()
177
+
178
+ # Optionally resume from a checkpoint
179
+ if args.resume:
180
+ # Use a local scope to avoid dangling references
181
+ def resume():
182
+ if os.path.isfile(args.resume):
183
+ print("=> loading checkpoint '{}'".format(args.resume))
184
+ checkpoint = torch.load(args.resume, map_location = lambda storage, loc: storage.cuda(args.gpu))
185
+ args.start_epoch = checkpoint['epoch']
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
+ crop_size = 299
201
+ val_size = 320 # I chose this value arbitrarily, we can adjust.
202
+ else:
203
+ crop_size = 224
204
+ val_size = 256
205
+
206
+ train_dataset = datasets.ImageFolder(
207
+ traindir,
208
+ transforms.Compose([
209
+ transforms.RandomResizedCrop(crop_size),
210
+ transforms.RandomHorizontalFlip(),
211
+ # transforms.ToTensor(), Too slow
212
+ # normalize,
213
+ ]))
214
+ val_dataset = datasets.ImageFolder(valdir, transforms.Compose([
215
+ transforms.Resize(val_size),
216
+ transforms.CenterCrop(crop_size),
217
+ ]))
218
+
219
+ train_sampler = None
220
+ val_sampler = None
221
+ if args.distributed:
222
+ train_sampler = torch.utils.data.distributed.DistributedSampler(train_dataset)
223
+ val_sampler = torch.utils.data.distributed.DistributedSampler(val_dataset)
224
+
225
+ train_loader = torch.utils.data.DataLoader(
226
+ train_dataset, batch_size=args.batch_size, shuffle=(train_sampler is None),
227
+ num_workers=args.workers, pin_memory=True, sampler=train_sampler, collate_fn=fast_collate)
228
+
229
+ val_loader = torch.utils.data.DataLoader(
230
+ val_dataset,
231
+ batch_size=args.batch_size, shuffle=False,
232
+ num_workers=args.workers, pin_memory=True,
233
+ sampler=val_sampler,
234
+ collate_fn=fast_collate)
235
+
236
+ if args.evaluate:
237
+ validate(val_loader, model, criterion)
238
+ return
239
+
240
+ for epoch in range(args.start_epoch, args.epochs):
241
+ if args.distributed:
242
+ train_sampler.set_epoch(epoch)
243
+
244
+ # train for one epoch
245
+ train(train_loader, model, criterion, optimizer, epoch)
246
+ if args.prof:
247
+ break
248
+ # evaluate on validation set
249
+ prec1 = validate(val_loader, model, criterion)
250
+
251
+ # remember best prec@1 and save checkpoint
252
+ if args.local_rank == 0:
253
+ is_best = prec1 > best_prec1
254
+ best_prec1 = max(prec1, best_prec1)
255
+ save_checkpoint({
256
+ 'epoch': epoch + 1,
257
+ 'arch': args.arch,
258
+ 'state_dict': model.state_dict(),
259
+ 'best_prec1': best_prec1,
260
+ 'optimizer' : optimizer.state_dict(),
261
+ }, is_best)
262
+
263
+ class data_prefetcher():
264
+ def __init__(self, loader):
265
+ self.loader = iter(loader)
266
+ self.stream = torch.cuda.Stream()
267
+ self.mean = torch.tensor([0.485 * 255, 0.456 * 255, 0.406 * 255]).cuda().view(1,3,1,1)
268
+ self.std = torch.tensor([0.229 * 255, 0.224 * 255, 0.225 * 255]).cuda().view(1,3,1,1)
269
+ # With Amp, it isn't necessary to manually convert data to half.
270
+ # if args.fp16:
271
+ # self.mean = self.mean.half()
272
+ # self.std = self.std.half()
273
+ self.preload()
274
+
275
+ def preload(self):
276
+ try:
277
+ self.next_input, self.next_target = next(self.loader)
278
+ except StopIteration:
279
+ self.next_input = None
280
+ self.next_target = None
281
+ return
282
+ with torch.cuda.stream(self.stream):
283
+ self.next_input = self.next_input.cuda(non_blocking=True)
284
+ self.next_target = self.next_target.cuda(non_blocking=True)
285
+ # With Amp, it isn't necessary to manually convert data to half.
286
+ # if args.fp16:
287
+ # self.next_input = self.next_input.half()
288
+ # else:
289
+ self.next_input = self.next_input.float()
290
+ self.next_input = self.next_input.sub_(self.mean).div_(self.std)
291
+
292
+ def next(self):
293
+ torch.cuda.current_stream().wait_stream(self.stream)
294
+ input = self.next_input
295
+ target = self.next_target
296
+ self.preload()
297
+ return input, target
298
+
299
+
300
+ def train(train_loader, model, criterion, optimizer, epoch):
301
+ batch_time = AverageMeter()
302
+ data_time = AverageMeter()
303
+ losses = AverageMeter()
304
+ top1 = AverageMeter()
305
+ top5 = AverageMeter()
306
+
307
+ # switch to train mode
308
+ model.train()
309
+ end = time.time()
310
+
311
+ run_info_dict = {"Iteration" : [],
312
+ "Loss" : [],
313
+ "Speed" : []}
314
+
315
+ prefetcher = data_prefetcher(train_loader)
316
+ input, target = prefetcher.next()
317
+ i = -1
318
+ while input is not None:
319
+ i += 1
320
+
321
+ # No learning rate warmup for this test, to expose bitwise inaccuracies more quickly
322
+ # adjust_learning_rate(optimizer, epoch, i, len(train_loader))
323
+
324
+ if args.prof:
325
+ if i > 10:
326
+ break
327
+ # measure data loading time
328
+ data_time.update(time.time() - end)
329
+
330
+ # compute output
331
+ output = model(input)
332
+ loss = criterion(output, target)
333
+
334
+ # measure accuracy and record loss
335
+ prec1, prec5 = accuracy(output.data, target, topk=(1, 5))
336
+
337
+ if args.distributed:
338
+ reduced_loss = reduce_tensor(loss.data)
339
+ prec1 = reduce_tensor(prec1)
340
+ prec5 = reduce_tensor(prec5)
341
+ else:
342
+ reduced_loss = loss.data
343
+
344
+ losses.update(to_python_float(reduced_loss), input.size(0))
345
+ top1.update(to_python_float(prec1), input.size(0))
346
+ top5.update(to_python_float(prec5), input.size(0))
347
+
348
+ # compute gradient and do SGD step
349
+ optimizer.zero_grad()
350
+
351
+ with amp.scale_loss(loss, optimizer) as scaled_loss:
352
+ scaled_loss.backward()
353
+
354
+ # for param in model.parameters():
355
+ # print(param.data.double().sum().item(), param.grad.data.double().sum().item())
356
+
357
+ # torch.cuda.synchronize()
358
+ torch.cuda.nvtx.range_push("step")
359
+ optimizer.step()
360
+ torch.cuda.nvtx.range_pop()
361
+
362
+ torch.cuda.synchronize()
363
+ # measure elapsed time
364
+ batch_time.update(time.time() - end)
365
+
366
+ end = time.time()
367
+
368
+ # If you decide to refactor this test, like examples/imagenet, to sample the loss every
369
+ # print_freq iterations, make sure to move this prefetching below the accuracy calculation.
370
+ input, target = prefetcher.next()
371
+
372
+ if i % args.print_freq == 0 and i > 1:
373
+ if args.local_rank == 0:
374
+ print('Epoch: [{0}][{1}/{2}]\t'
375
+ 'Time {batch_time.val:.3f} ({batch_time.avg:.3f})\t'
376
+ 'Speed {3:.3f} ({4:.3f})\t'
377
+ 'Data {data_time.val:.3f} ({data_time.avg:.3f})\t'
378
+ 'Loss {loss.val:.10f} ({loss.avg:.4f})\t'
379
+ 'Prec@1 {top1.val:.3f} ({top1.avg:.3f})\t'
380
+ 'Prec@5 {top5.val:.3f} ({top5.avg:.3f})'.format(
381
+ epoch, i, len(train_loader),
382
+ args.world_size * args.batch_size / batch_time.val,
383
+ args.world_size * args.batch_size / batch_time.avg,
384
+ batch_time=batch_time,
385
+ data_time=data_time, loss=losses, top1=top1, top5=top5))
386
+ run_info_dict["Iteration"].append(i)
387
+ run_info_dict["Loss"].append(losses.val)
388
+ run_info_dict["Speed"].append(args.world_size * args.batch_size / batch_time.val)
389
+ if len(run_info_dict["Loss"]) == args.prints_to_process:
390
+ if args.local_rank == 0:
391
+ torch.save(run_info_dict,
392
+ str(args.has_ext) + "_" + str(args.opt_level) + "_" +
393
+ str(args.loss_scale) + "_" + str(args.keep_batchnorm_fp32) + "_" +
394
+ str(args.fused_adam))
395
+ quit()
396
+
397
+
398
+ def validate(val_loader, model, criterion):
399
+ batch_time = AverageMeter()
400
+ losses = AverageMeter()
401
+ top1 = AverageMeter()
402
+ top5 = AverageMeter()
403
+
404
+ # switch to evaluate mode
405
+ model.eval()
406
+
407
+ end = time.time()
408
+
409
+ prefetcher = data_prefetcher(val_loader)
410
+ input, target = prefetcher.next()
411
+ i = -1
412
+ while input is not None:
413
+ i += 1
414
+
415
+ # compute output
416
+ with torch.no_grad():
417
+ output = model(input)
418
+ loss = criterion(output, target)
419
+
420
+ # measure accuracy and record loss
421
+ prec1, prec5 = accuracy(output.data, target, topk=(1, 5))
422
+
423
+ if args.distributed:
424
+ reduced_loss = reduce_tensor(loss.data)
425
+ prec1 = reduce_tensor(prec1)
426
+ prec5 = reduce_tensor(prec5)
427
+ else:
428
+ reduced_loss = loss.data
429
+
430
+ losses.update(to_python_float(reduced_loss), input.size(0))
431
+ top1.update(to_python_float(prec1), input.size(0))
432
+ top5.update(to_python_float(prec5), input.size(0))
433
+
434
+ # measure elapsed time
435
+ batch_time.update(time.time() - end)
436
+ end = time.time()
437
+
438
+ if args.local_rank == 0 and i % args.print_freq == 0:
439
+ print('Test: [{0}/{1}]\t'
440
+ 'Time {batch_time.val:.3f} ({batch_time.avg:.3f})\t'
441
+ 'Speed {2:.3f} ({3:.3f})\t'
442
+ 'Loss {loss.val:.4f} ({loss.avg:.4f})\t'
443
+ 'Prec@1 {top1.val:.3f} ({top1.avg:.3f})\t'
444
+ 'Prec@5 {top5.val:.3f} ({top5.avg:.3f})'.format(
445
+ i, len(val_loader),
446
+ args.world_size * args.batch_size / batch_time.val,
447
+ args.world_size * args.batch_size / batch_time.avg,
448
+ batch_time=batch_time, loss=losses,
449
+ top1=top1, top5=top5))
450
+
451
+ input, target = prefetcher.next()
452
+
453
+ print(' * Prec@1 {top1.avg:.3f} Prec@5 {top5.avg:.3f}'
454
+ .format(top1=top1, top5=top5))
455
+
456
+ return top1.avg
457
+
458
+
459
+ def save_checkpoint(state, is_best, filename='checkpoint.pth.tar'):
460
+ torch.save(state, filename)
461
+ if is_best:
462
+ shutil.copyfile(filename, 'model_best.pth.tar')
463
+
464
+
465
+ class AverageMeter(object):
466
+ """Computes and stores the average and current value"""
467
+ def __init__(self):
468
+ self.reset()
469
+
470
+ def reset(self):
471
+ self.val = 0
472
+ self.avg = 0
473
+ self.sum = 0
474
+ self.count = 0
475
+
476
+ def update(self, val, n=1):
477
+ self.val = val
478
+ self.sum += val * n
479
+ self.count += n
480
+ self.avg = self.sum / self.count
481
+
482
+
483
+ def adjust_learning_rate(optimizer, epoch, step, len_epoch):
484
+ """LR schedule that should yield 76% converged accuracy with batch size 256"""
485
+ factor = epoch // 30
486
+
487
+ if epoch >= 80:
488
+ factor = factor + 1
489
+
490
+ lr = args.lr*(0.1**factor)
491
+
492
+ """Warmup"""
493
+ if epoch < 5:
494
+ lr = lr*float(1 + step + epoch*len_epoch)/(5.*len_epoch)
495
+
496
+ # if(args.local_rank == 0):
497
+ # print("epoch = {}, step = {}, lr = {}".format(epoch, step, lr))
498
+
499
+ for param_group in optimizer.param_groups:
500
+ param_group['lr'] = lr
501
+
502
+
503
+ def accuracy(output, target, topk=(1,)):
504
+ """Computes the precision@k for the specified values of k"""
505
+ maxk = max(topk)
506
+ batch_size = target.size(0)
507
+
508
+ _, pred = output.topk(maxk, 1, True, True)
509
+ pred = pred.t()
510
+ correct = pred.eq(target.view(1, -1).expand_as(pred))
511
+
512
+ res = []
513
+ for k in topk:
514
+ correct_k = correct[:k].view(-1).float().sum(0, keepdim=True)
515
+ res.append(correct_k.mul_(100.0 / batch_size))
516
+ return res
517
+
518
+
519
+ def reduce_tensor(tensor):
520
+ rt = tensor.clone()
521
+ dist.all_reduce(rt, op=dist.reduce_op.SUM)
522
+ rt /= args.world_size
523
+ return rt
524
+
525
+ if __name__ == '__main__':
526
+ main()