原文:https://blog.csdn.net/ei1990/article/details/77948001
1、tf.train.Supervisor()
import tensorflow as tf
import numpy as np
import os
log_path = 'ckptdir/'
log_name = 'liner.ckpt'
x_data = np.random.rand(100).astype(np.float32)
y_data = x_data*0.1 + 0.3
w = tf.Variable(tf.random_normal([1]))
b = tf.Variable(tf.zeros([1]))
y = w*x_data + b
loss = tf.reduce_mean(tf.square(y-y_data))
train = tf.train.AdamOptimizer(0.5).minimize(loss)
tf.summary.scalar('loss', loss)
saver = tf.train.Saver()
init = tf.global_variables_initializer()
merged = tf.summary.merge_all()
sv = tf.train.Supervisor(logdir=log_path, init_op=init) # logdir用來保存checkpoint和summary
saver = sv.saver # 創建saver
with sv.managed_session() as sess: # 會自動去logdir中去找checkpoint,如果沒有的話,自動執行初始化
# sess.run(init)
# if len(os.listdir(log_path)) != 0:
# saver.restore(sess, os.path.join(log_path, log_name))
for step in range(201):
sess.run(train)
if step%50 == 0:
print(step, sess.run(w), sess.run(b))
merged_summary = sess.run(merged)
sv.summary_computed(sess, merged_summary,global_step=step)
saver.save(sess, os.path.join(log_path, 'liner.ckpt'))
從上面代碼可以看出,Supervisor幫助我們處理一些事情
(1)自動去checkpoint加載數據或初始化數據
(2)自身有一個Saver,可以用來保存checkpoint
(3)有一個summary_computed用來保存Summary
所以,我們就不需要:
(1)手動初始化或從checkpoint中加載數據
(2)不需要創建Saver,使用sv內部的就可以
(3)不需要創建summary writer
2、tf.train.Saver()
import tensorflow as tf
import numpy as np
import os
log_path = 'ckptdir'
log_name = 'liner.ckpt'
x_data = np.random.rand(100).astype(np.float32)
y_data = x_data*0.1 + 0.3
w = tf.Variable(tf.random_normal([1]))
b = tf.Variable(tf.zeros([1]))
y = w*x_data + b
loss = tf.reduce_mean(tf.square(y-y_data))
train = tf.train.AdamOptimizer(0.5).minimize(loss)
tf.summary.scalar('loss', loss)
saver = tf.train.Saver()
init = tf.global_variables_initializer()
merged = tf.summary.merge_all()
with tf.Session() as sess:
sess.run(init)
print("loading model from checkpoint")
checkpoint = tf.train.latest_checkpoint(os.path.join(log_path, log_name))
restore_saver.restore(sess, checkpoint)
#if len(os.listdir(log_path)) != 0:
# saver.restore(sess, os.path.join(log_path, log_name))
for step in range(201):
sess.run(train)
if step%50 ==0:
print(step, sess.run(w), sess.run(b))
summary_writer = tf.summary.FileWriter(log_path, sess.graph)
summary_all = sess.run(merged)
summary_writer.add_summary(summary_all)
summary_writer.close()
saver.save(sess, os.path.join(log_path, 'liner.ckpt'))