Supervisor does not initialize parameters succeed - tensorflow

Question

It throws an exception when I tried to initialize parameters with tf.train.Supervisor where the net is constructed with tensorlayer. The code is like this:
init_op = tf.global_variables_initializer()
saver = tf.train.Saver()
config = tf.ConfigProto()
config.gpu_options.allow_growth = True
sv = tf.train.Supervisor(logdir=FLAGS.summary_dir, save_summaries_secs=0, saver=None)
with sv.managed_session(config=config) as sess:
init_ = sess.run(init_op)
net.print_params()
net.print_layers()
tl.layers.print_all_variables()
and the exception is:
Cannot evaluate tensor using `eval()`: No default session is registered. Use `with sess.as_default()` or pass an explicit session to `eval(session=sess)`
Traceback (most recent call last):
File "/home/recsys/anaconda3/envs/tf1.2/lib/python3.6/site-packages/tensorlayer/layers.py", line 309, in print_params
val = p.eval()
File "/home/recsys/anaconda3/envs/tf1.2/lib/python3.6/site-packages/tensorflow/python/ops/variables.py", line 463, in eval
return self._variable.eval(session=session)
File "/home/recsys/anaconda3/envs/tf1.2/lib/python3.6/site-packages/tensorflow/python/framework/ops.py", line 606, in eval
return _eval_using_default_session(self, feed_dict, self.graph, session)
File "/home/recsys/anaconda3/envs/tf1.2/lib/python3.6/site-packages/tensorflow/python/framework/ops.py", line 3914, in _eval_using_default_session
raise ValueError("Cannot evaluate tensor using `eval()`: No default "
ValueError: Cannot evaluate tensor using `eval()`: No default session is registered. Use `with sess.as_default()` or pass an explicit session to `eval(session=sess)`
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
File "MainEntryPtb.py", line 65, in <module>
train_rnn(FLAGS)
File "/home/recsys/wangjian/learntf/TFTemplate/examples/ptb.py", line 122, in train_rnn
net.print_params()
File "/home/recsys/anaconda3/envs/tf1.2/lib/python3.6/site-packages/tensorlayer/layers.py", line 313, in print_params
raise Exception("Hint: print params details after tl.layers.initialize_global_variables(sess) or use network.print_params(False).")
Exception: Hint: print params details after tl.layers.initialize_global_variables(sess) or use network.print_params(False).
It seems that when I run initialize op init_ = sess.run(init_op) it does not really work as if parameters are initialized succeed net.print_params() would not throw an exception. I also tried sv = tf.train.Supervisor(logdir=FLAGS.summary_dir, save_summaries_secs=0, saver=None, init_op=tf.global_variables_initializer()) to initialize parameters, but it also failed.
I use tensorflow v1.2.1 and python3.6

Answer 1

This GitHub issue has clearly explained this problem.
This is not a bug, neither nor "Supervisor does not initialize parameters succeed".
You should just change your sess into interactivesession or use with sess.as_default, then this problem will be solved.
If you want to know why this problem occurs,you should refer to the tensorlayer source code, in the definition of print_params has the :
val = p.eval(session=session)
clearly eval only used for interactivesession or with sess.as_default