File size: 8,684 Bytes
3589275
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
import os
import time

import torch

from src.args import parse_arguments
from src.datasets.common import get_dataloader, maybe_dictionarize
from src.datasets.registry import get_dataset
from src.distributed import cleanup_ddp, distribute_loader, is_main_process, setup_ddp
from src.eval import eval_single_dataset
from src.heads import get_classification_head
from src.linearize import LinearizedImageEncoder
from src.modeling import ImageClassifier, ImageEncoder
from src.attention_only_finetune import AttentionOnlyFinetuneEncoder
from src.utils import LabelSmoothing, cosine_lr, accuracy


def finetune(rank, args):
    setup_ddp(rank, args.world_size, port=args.port)

    train_dataset = args.train_dataset
    ckpdir = os.path.join(args.save, train_dataset)

    valid_modes = [
        "standard", "standard_ortho",
        "linear", "linear_ortho",
        "linear-2", "linear-2_ortho",
    ]
    assert args.finetuning_mode in valid_modes, f"Mode {args.finetuning_mode} not supported."

    is_linearized = args.finetuning_mode in ("linear", "linear_ortho")
    is_linear2 = args.finetuning_mode in ("linear-2", "linear-2_ortho")
    is_standard_ortho = args.finetuning_mode == "standard_ortho"
    is_linear_ortho = args.finetuning_mode == "linear_ortho"
    is_linear2_ortho = args.finetuning_mode == "linear-2_ortho"
    needs_ortho = is_standard_ortho or is_linear_ortho or is_linear2_ortho

    print(f"Using fine-tuning mode: {args.finetuning_mode}")
    if needs_ortho and args.ortho_lambda > 0:
        print(f"  -> With OrthoReg (lambda={args.ortho_lambda})")

    mode_prefix_map = {
        "standard": "",
        "standard_ortho": "standard_ortho",
        "linear": "linear",
        "linear_ortho": "linear_ortho",
        "linear-2": "linear-2",
        "linear-2_ortho": "linear-2_ortho",
    }
    mode_prefix = mode_prefix_map[args.finetuning_mode]

    ft_path = os.path.join(ckpdir, f"{mode_prefix}_finetuned.pt" if mode_prefix else "finetuned.pt")
    zs_path = os.path.join(ckpdir, f"{mode_prefix}_zeroshot.pt" if mode_prefix else "zeroshot.pt")

    if os.path.exists(zs_path) and os.path.exists(ft_path):
        print(f"Skipping fine-tuning because {ft_path} exists.")
        return zs_path, ft_path

    assert train_dataset is not None, "Please provide a training dataset."

    if args.load is not None and args.load.endswith("pt"):
        if is_linearized:
            image_encoder = LinearizedImageEncoder.load(args.load)
        elif is_linear2:
            image_encoder = AttentionOnlyFinetuneEncoder.load(args.load, args)
        else:
            image_encoder = ImageEncoder.load(args.load)
    else:
        print("Building image encoder.")
        if is_linearized:
            image_encoder = LinearizedImageEncoder(args, keep_lang=False)
        elif is_linear2:
            image_encoder = AttentionOnlyFinetuneEncoder(args, keep_lang=False)
        else:
            image_encoder = ImageEncoder(args)

    # Save a frozen copy of pretrained weights for ortho loss (standard_ortho / linear-2_ortho)
    pretrained_state_dict_ref = None
    if is_standard_ortho or is_linear2_ortho:
        print("Saving pretrained state dict reference for ortho loss.")
        pretrained_state_dict_ref = {
            k: v.clone().detach() for k, v in image_encoder.model.state_dict().items()
        }

    classification_head = get_classification_head(args, train_dataset)
    model = ImageClassifier(image_encoder, classification_head)
    model.freeze_head()
    model = model.cuda()

    preprocess_fn = model.train_preprocess
    print_every = 100

    dataset = get_dataset(
        train_dataset,
        preprocess_fn,
        location=args.data_location,
        batch_size=args.batch_size,
    )
    data_loader = get_dataloader(dataset, is_train=True, args=args, image_encoder=None)
    num_batches = len(dataset.train_loader)

    ddp_loader = distribute_loader(data_loader)
    ddp_model = torch.nn.parallel.DistributedDataParallel(
        model,
        device_ids=[rank],
        find_unused_parameters=True,
        output_device=rank,
    )

    loss_fn = LabelSmoothing(args.ls) if args.ls > 0 else torch.nn.CrossEntropyLoss()

    params = [p for p in ddp_model.parameters() if p.requires_grad]
    optimizer = torch.optim.AdamW(params, lr=args.lr, weight_decay=args.wd)
    scheduler = cosine_lr(
        optimizer,
        args.lr,
        args.warmup_length,
        args.epochs * num_batches // args.num_grad_accumulation,
    )

    if args.save is not None and is_main_process():
        os.makedirs(ckpdir, exist_ok=True)
        ddp_model.module.image_encoder.save(zs_path)

    for epoch in range(args.epochs):
        ddp_model.train()

        for i, batch in enumerate(ddp_loader):
            start_time = time.time()
            step = (
                i // args.num_grad_accumulation
                + epoch * num_batches // args.num_grad_accumulation
            )

            batch = maybe_dictionarize(batch)
            inputs = batch["images"].cuda()
            labels = batch["labels"].cuda()
            data_time = time.time() - start_time

            ortho_loss = 0.0
            if needs_ortho and args.ortho_lambda > 0:
                logits, ortho_loss = ddp_model(
                    inputs,
                    calculate_ortho_loss=True,
                    pretrained_state_dict=pretrained_state_dict_ref,
                )
            else:
                logits = ddp_model(inputs)

            classification_loss = loss_fn(logits, labels)
            loss = classification_loss + args.ortho_lambda * ortho_loss

            (acc1,) = accuracy(logits, labels, topk=(1,))
            acc1 /= labels.size(0)

            loss.backward()

            if (i + 1) % args.num_grad_accumulation == 0:
                scheduler(step)
                torch.nn.utils.clip_grad_norm_(params, 1.0)
                optimizer.step()
                optimizer.zero_grad()

            batch_time = time.time() - start_time

            if (
                args.checkpoint_every > 0
                and step % args.checkpoint_every == 0
                and is_main_process()
            ):
                ckpt_name = f"{mode_prefix}_checkpoint_{step}.pt" if mode_prefix else f"checkpoint_{step}.pt"
                ddp_model.module.image_encoder.save(os.path.join(ckpdir, ckpt_name))

            if (
                step % print_every == 0
                and ((i + 1) % args.num_grad_accumulation == 0)
                and is_main_process()
            ):
                percent_complete = 100 * i / len(ddp_loader)
                log_msg = (
                    f"Train Epoch: {epoch} [{percent_complete:.0f}%]\t"
                    f"Total Loss: {loss.item():.6f}\t"
                    f"CE Loss: {classification_loss.item():.6f}\t"
                )
                if needs_ortho and args.ortho_lambda > 0:
                    log_msg += f"Ortho Loss: {ortho_loss.item():.6f}\t"
                log_msg += f"Acc@1: {100*acc1:.2f}%\tData (t) {data_time:.3f}"
                print(log_msg, flush=True)

    if is_main_process():
        image_encoder = ddp_model.module.image_encoder
        eval_single_dataset(image_encoder, train_dataset, args)

    if args.save is not None and is_main_process():
        image_encoder.save(ft_path)
        return zs_path, ft_path

    cleanup_ddp()


if __name__ == "__main__":
    train_datasets = [
        "Cars",
        "DTD",
        "EuroSAT",
        "GTSRB",
        "MNIST",
        "RESISC45",
        "SUN397",
        "SVHN",
    ]
    epochs = {
        "Cars": 35,
        "DTD": 76,
        "EuroSAT": 12,
        "GTSRB": 11,
        "MNIST": 5,
        "RESISC45": 15,
        "SUN397": 14,
        "SVHN": 4,
    }

    for dataset in train_datasets:
        args = parse_arguments()

        args.epochs = epochs[dataset]
        args.train_dataset = dataset + "Val"

        args.batch_size = 64 if args.model == "ViT-L-14" else 128
        args.num_grad_accumulation = 2 if args.model == "ViT-L-14" else 1

        if 'ortho' in args.finetuning_mode:
            args.save = f"checkpoints_{args.seed}/{args.finetuning_mode}_{args.lr}_lambda{args.ortho_lambda}_{args.model}"
        else:
            if args.seed is not None:
                args.save = f"checkpoints_{args.seed}/{args.finetuning_mode}_{args.lr}_{args.model}"
            else:
                args.save = f"checkpoints/{args.finetuning_mode}_{args.lr}_{args.model}"

        print("=" * 100)
        print(f"Finetuning {args.model} on {dataset}")
        print("=" * 100)
        torch.multiprocessing.spawn(finetune, args=(args,), nprocs=args.world_size)