File size: 4,694 Bytes
4021124
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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
# Licensed under the Apache License, Version 2.0 (the "License"). You
# may not use this file except in compliance with the License. A copy of
# the License is located at
#
#     http://aws.amazon.com/apache2.0/
#
# or in the "license" file accompanying this file. This file is
# distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF
# ANY KIND, either express or implied. See the License for the specific
# language governing permissions and limitations under the License.
from __future__ import absolute_import

import argparse
import gzip
import json
import logging
import os
import struct

import mxnet as mx
import numpy as np


def load_data(path):
    with gzip.open(find_file(path, "labels.gz")) as flbl:
        struct.unpack(">II", flbl.read(8))
        labels = np.fromstring(flbl.read(), dtype=np.int8)
    with gzip.open(find_file(path, "images.gz")) as fimg:
        _, _, rows, cols = struct.unpack(">IIII", fimg.read(16))
        images = np.fromstring(fimg.read(), dtype=np.uint8).reshape(len(labels), rows, cols)
        images = images.reshape(images.shape[0], 1, 28, 28).astype(np.float32) / 255
    return labels, images


def find_file(root_path, file_name):
    for root, dirs, files in os.walk(root_path):
        if file_name in files:
            return os.path.join(root, file_name)


def build_graph():
    data = mx.sym.var("data")
    data = mx.sym.flatten(data=data)
    fc1 = mx.sym.FullyConnected(data=data, num_hidden=128)
    act1 = mx.sym.Activation(data=fc1, act_type="relu")
    fc2 = mx.sym.FullyConnected(data=act1, num_hidden=64)
    act2 = mx.sym.Activation(data=fc2, act_type="relu")
    fc3 = mx.sym.FullyConnected(data=act2, num_hidden=10)
    return mx.sym.SoftmaxOutput(data=fc3, name="softmax")


def get_train_context(num_gpus):
    if num_gpus:
        return [mx.gpu(i) for i in range(num_gpus)]
    else:
        return mx.cpu()


def train(
    batch_size,
    epochs,
    learning_rate,
    num_gpus,
    training_channel,
    testing_channel,
    hosts,
    current_host,
    model_dir,
):
    (train_labels, train_images) = load_data(training_channel)
    (test_labels, test_images) = load_data(testing_channel)

    # Data parallel training - shard the data so each host
    # only trains on a subset of the total data.
    shard_size = len(train_images) // len(hosts)
    for i, host in enumerate(hosts):
        if host == current_host:
            start = shard_size * i
            end = start + shard_size
            break

    train_iter = mx.io.NDArrayIter(
        train_images[start:end], train_labels[start:end], batch_size, shuffle=True
    )
    val_iter = mx.io.NDArrayIter(test_images, test_labels, batch_size)

    logging.getLogger().setLevel(logging.DEBUG)

    kvstore = "local" if len(hosts) == 1 else "dist_sync"

    mlp_model = mx.mod.Module(symbol=build_graph(), context=get_train_context(num_gpus))
    mlp_model.fit(
        train_iter,
        eval_data=val_iter,
        kvstore=kvstore,
        optimizer="sgd",
        optimizer_params={"learning_rate": learning_rate},
        eval_metric="acc",
        batch_end_callback=mx.callback.Speedometer(batch_size, 100),
        num_epoch=epochs,
    )

    if len(hosts) == 1 or current_host == hosts[0]:
        save(model_dir, mlp_model)


def save(model_dir, model):
    model.symbol.save(os.path.join(model_dir, "model-symbol.json"))
    model.save_params(os.path.join(model_dir, "model-0000.params"))

    signature = [
        {"name": data_desc.name, "shape": [dim for dim in data_desc.shape]}
        for data_desc in model.data_shapes
    ]
    with open(os.path.join(model_dir, "model-shapes.json"), "w") as f:
        json.dump(signature, f)


if __name__ == "__main__":
    parser = argparse.ArgumentParser()

    parser.add_argument("--batch-size", type=int, default=100)
    parser.add_argument("--epochs", type=int, default=10)
    parser.add_argument("--learning-rate", type=float, default=0.1)

    parser.add_argument("--model-dir", type=str, default=os.environ["SM_MODEL_DIR"])
    parser.add_argument("--train", type=str, default=os.environ["SM_CHANNEL_TRAIN"])
    parser.add_argument("--test", type=str, default=os.environ["SM_CHANNEL_TEST"])

    parser.add_argument("--current-host", type=str, default=os.environ["SM_CURRENT_HOST"])
    parser.add_argument("--hosts", type=list, default=json.loads(os.environ["SM_HOSTS"]))

    args = parser.parse_args()

    num_gpus = int(os.environ["SM_NUM_GPUS"])

    train(
        args.batch_size,
        args.epochs,
        args.learning_rate,
        num_gpus,
        args.train,
        args.test,
        args.hosts,
        args.current_host,
        args.model_dir,
    )