File size: 10,908 Bytes
4efbc62
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
# EfficientViT: Multi-Scale Linear Attention for High-Resolution Dense Prediction
# Han Cai, Junyan Li, Muyan Hu, Chuang Gan, Song Han
# International Conference on Computer Vision (ICCV), 2023

import os

import torch
import torch.nn as nn

from efficientvit.apps.data_provider import DataProvider, parse_image_size
from efficientvit.apps.trainer.run_config import RunConfig
from efficientvit.apps.utils import (EMA, dist_barrier, get_dist_local_rank,
                                     is_master)
from efficientvit.models.nn.norm import reset_bn
from efficientvit.models.utils import is_parallel, load_state_dict_from_file

__all__ = ["Trainer"]


class Trainer:
    def __init__(self, path: str, model: nn.Module, data_provider: DataProvider):
        self.path = os.path.realpath(os.path.expanduser(path))
        self.model = model.cuda()
        self.data_provider = data_provider

        self.ema = None

        self.checkpoint_path = os.path.join(self.path, "checkpoint")
        self.logs_path = os.path.join(self.path, "logs")
        for path in [self.path, self.checkpoint_path, self.logs_path]:
            os.makedirs(path, exist_ok=True)

        self.best_val = 0.0
        self.start_epoch = 0

    @property
    def network(self) -> nn.Module:
        return self.model.module if is_parallel(self.model) else self.model

    @property
    def eval_network(self) -> nn.Module:
        if self.ema is None:
            model = self.model
        else:
            model = self.ema.shadows
        model = model.module if is_parallel(model) else model
        return model

    def write_log(self, log_str, prefix="valid", print_log=True, mode="a") -> None:
        if is_master():
            fout = open(os.path.join(self.logs_path, f"{prefix}.log"), mode)
            fout.write(log_str + "\n")
            fout.flush()
            fout.close()
            if print_log:
                print(log_str)

    def save_model(
        self,
        checkpoint=None,
        only_state_dict=True,
        epoch=0,
        model_name=None,
    ) -> None:
        if is_master():
            if checkpoint is None:
                if only_state_dict:
                    checkpoint = {"state_dict": self.network.state_dict()}
                else:
                    checkpoint = {
                        "state_dict": self.network.state_dict(),
                        "epoch": epoch,
                        "best_val": self.best_val,
                        "optimizer": self.optimizer.state_dict(),
                        "lr_scheduler": self.lr_scheduler.state_dict(),
                        "ema": self.ema.state_dict() if self.ema is not None else None,
                        "scaler": self.scaler.state_dict() if self.fp16 else None,
                    }

            model_name = model_name or "checkpoint.pt"

            latest_fname = os.path.join(self.checkpoint_path, "latest.txt")
            model_path = os.path.join(self.checkpoint_path, model_name)
            with open(latest_fname, "w") as _fout:
                _fout.write(model_path + "\n")
            torch.save(checkpoint, model_path)

    def load_model(self, model_fname=None) -> None:
        latest_fname = os.path.join(self.checkpoint_path, "latest.txt")
        if model_fname is None and os.path.exists(latest_fname):
            with open(latest_fname, "r") as fin:
                model_fname = fin.readline()
                if len(model_fname) > 0 and model_fname[-1] == "\n":
                    model_fname = model_fname[:-1]
        try:
            if model_fname is None:
                model_fname = f"{self.checkpoint_path}/checkpoint.pt"
            elif not os.path.exists(model_fname):
                model_fname = f"{self.checkpoint_path}/{os.path.basename(model_fname)}"
                if not os.path.exists(model_fname):
                    model_fname = f"{self.checkpoint_path}/checkpoint.pt"
            print(f"=> loading checkpoint {model_fname}")
            checkpoint = load_state_dict_from_file(model_fname, False)
        except Exception:
            self.write_log(f"fail to load checkpoint from {self.checkpoint_path}")
            return

        # load checkpoint
        self.network.load_state_dict(checkpoint["state_dict"], strict=False)
        log = []
        if "epoch" in checkpoint:
            self.start_epoch = checkpoint["epoch"] + 1
            self.run_config.update_global_step(self.start_epoch)
            log.append(f"epoch={self.start_epoch - 1}")
        if "best_val" in checkpoint:
            self.best_val = checkpoint["best_val"]
            log.append(f"best_val={self.best_val:.2f}")
        if "optimizer" in checkpoint:
            self.optimizer.load_state_dict(checkpoint["optimizer"])
            log.append("optimizer")
        if "lr_scheduler" in checkpoint:
            self.lr_scheduler.load_state_dict(checkpoint["lr_scheduler"])
            log.append("lr_scheduler")
        if "ema" in checkpoint and self.ema is not None:
            self.ema.load_state_dict(checkpoint["ema"])
            log.append("ema")
        if "scaler" in checkpoint and self.fp16:
            self.scaler.load_state_dict(checkpoint["scaler"])
            log.append("scaler")
        self.write_log("Loaded: " + ", ".join(log))

    """ validate """

    def reset_bn(
        self,
        network: nn.Module or None = None,
        subset_size: int = 16000,
        subset_batch_size: int = 100,
        data_loader=None,
        progress_bar=False,
    ) -> None:
        network = network or self.network
        if data_loader is None:
            data_loader = []
            for data in self.data_provider.build_sub_train_loader(
                subset_size, subset_batch_size
            ):
                if isinstance(data, list):
                    data_loader.append(data[0])
                elif isinstance(data, dict):
                    data_loader.append(data["data"])
                elif isinstance(data, torch.Tensor):
                    data_loader.append(data)
                else:
                    raise NotImplementedError

        network.eval()
        reset_bn(
            network,
            data_loader,
            sync=True,
            progress_bar=progress_bar,
        )

    def _validate(self, model, data_loader, epoch) -> dict[str, any]:
        raise NotImplementedError

    def validate(
        self, model=None, data_loader=None, is_test=True, epoch=0
    ) -> dict[str, any]:
        model = model or self.eval_network
        if data_loader is None:
            if is_test:
                data_loader = self.data_provider.test
            else:
                data_loader = self.data_provider.valid

        model.eval()
        return self._validate(model, data_loader, epoch)

    def multires_validate(
        self,
        model=None,
        data_loader=None,
        is_test=True,
        epoch=0,
        eval_image_size=None,
    ) -> dict[str, dict[str, any]]:
        eval_image_size = eval_image_size or self.run_config.eval_image_size
        eval_image_size = eval_image_size or self.data_provider.image_size
        model = model or self.eval_network

        if not isinstance(eval_image_size, list):
            eval_image_size = [eval_image_size]

        output_dict = {}
        for r in eval_image_size:
            self.data_provider.assign_active_image_size(parse_image_size(r))
            if self.run_config.reset_bn:
                self.reset_bn(
                    network=model,
                    subset_size=self.run_config.reset_bn_size,
                    subset_batch_size=self.run_config.reset_bn_batch_size,
                    progress_bar=True,
                )
            output_dict[f"r{r}"] = self.validate(model, data_loader, is_test, epoch)
        return output_dict

    """ training """

    def prep_for_training(
        self, run_config: RunConfig, ema_decay: float or None = None, fp16=False
    ) -> None:
        self.run_config = run_config
        self.model = nn.parallel.DistributedDataParallel(
            self.model.cuda(),
            device_ids=[get_dist_local_rank()],
            static_graph=True,
        )

        self.run_config.global_step = 0
        self.run_config.batch_per_epoch = len(self.data_provider.train)
        assert self.run_config.batch_per_epoch > 0, "Training set is empty"

        # build optimizer
        self.optimizer, self.lr_scheduler = self.run_config.build_optimizer(self.model)

        if ema_decay is not None:
            self.ema = EMA(self.network, ema_decay)

        # fp16
        self.fp16 = fp16
        self.scaler = torch.cuda.amp.GradScaler(enabled=self.fp16)

    def sync_model(self):
        print("Sync model")
        self.save_model(model_name="sync.pt")
        dist_barrier()
        checkpoint = torch.load(
            os.path.join(self.checkpoint_path, "sync.pt"), map_location="cpu"
        )
        dist_barrier()
        if is_master():
            os.remove(os.path.join(self.checkpoint_path, "sync.pt"))
        dist_barrier()

        # load checkpoint
        self.network.load_state_dict(checkpoint["state_dict"], strict=False)
        if "optimizer" in checkpoint:
            self.optimizer.load_state_dict(checkpoint["optimizer"])
        if "lr_scheduler" in checkpoint:
            self.lr_scheduler.load_state_dict(checkpoint["lr_scheduler"])
        if "ema" in checkpoint and self.ema is not None:
            self.ema.load_state_dict(checkpoint["ema"])
        if "scaler" in checkpoint and self.fp16:
            self.scaler.load_state_dict(checkpoint["scaler"])

    def before_step(self, feed_dict: dict[str, any]) -> dict[str, any]:
        for key in feed_dict:
            if isinstance(feed_dict[key], torch.Tensor):
                feed_dict[key] = feed_dict[key].cuda()
        return feed_dict

    def run_step(self, feed_dict: dict[str, any]) -> dict[str, any]:
        raise NotImplementedError

    def after_step(self) -> None:
        self.scaler.unscale_(self.optimizer)
        # gradient clip
        if self.run_config.grad_clip is not None:
            torch.nn.utils.clip_grad_value_(
                self.model.parameters(), self.run_config.grad_clip
            )
        # update
        self.scaler.step(self.optimizer)
        self.scaler.update()

        self.lr_scheduler.step()
        self.run_config.step()
        # update ema
        if self.ema is not None:
            self.ema.step(self.network, self.run_config.global_step)

    def _train_one_epoch(self, epoch: int) -> dict[str, any]:
        raise NotImplementedError

    def train_one_epoch(self, epoch: int) -> dict[str, any]:
        self.model.train()

        self.data_provider.set_epoch(epoch)

        train_info_dict = self._train_one_epoch(epoch)

        return train_info_dict

    def train(self) -> None:
        raise NotImplementedError