def run_eval(self):
"""Repeatedly runs eval iterations, logging to screen and writing summaries. Saves the model with the best loss seen so far."""
self.model.build_graph() # build the graph
saver = tf.train.Saver(max_to_keep=3) # we will keep 3 best checkpoints at a time
sess = tf.Session(config=util.get_config())
if FLAGS.embedding:
sess.run(tf.global_variables_initializer(),feed_dict={self.model.embedding_place:self.word_vector})
#eval_dir = os.path.join(FLAGS.log_root, "eval") # make a subdir of the root dir for eval data
eval_dir = os.path.join(FLAGS.log_root, "eval_{}".format(
"rouge" if FLAGS.rouge_based_eval else "loss")) # make a subdir of the root dir for eval data
bestmodel_save_path = os.path.join(eval_dir, 'bestmodel') # this is where checkpoints of best models are saved
self.summary_writer = tf.summary.FileWriter(eval_dir)
if FLAGS.ac_training:
tf.logging.info('DDQN building graph')
t1 = time.time()
dqn_graph = tf.Graph()
with dqn_graph.as_default():
self.dqn.build_graph() # build dqn graph
tf.logging.info('building current network took {} seconds'.format(time.time()-t1))
self.dqn_target.build_graph() # build dqn target graph
tf.logging.info('building target network took {} seconds'.format(time.time()-t1))
dqn_saver = tf.train.Saver(max_to_keep=3) # keep 3 checkpoints at a time
dqn_sess = tf.Session(config=util.get_config())
dqn_train_step = 0
replay_buffer = ReplayBuffer(self.dqn_hps)
running_avg_loss = 0 # the eval job keeps a smoother, running average loss to tell it when to implement early stopping
best_loss = self.restore_best_eval_model() # will hold the best loss achieved so far
train_step = 0
decay = 0.99
while True:
_ = util.load_ckpt(saver, sess) # load a new checkpoint
if FLAGS.ac_training:
_ = util.load_dqn_ckpt(dqn_saver, dqn_sess) # load a new checkpoint
processed_batch = 0
avg_losses = []
greedy_rouges = []
sampled_rouges = []
# evaluate for 100 * batch_size before comparing the loss
# we do this due to memory constraint, best to run eval on different machines with large batch size
while processed_batch < FLAGS.eval_interval*FLAGS.batch_size:
processed_batch += FLAGS.batch_size
batch = full_batch = self.full_batcher.next_batch()
if FLAGS.rl_training:
partial_batch = self.partial_batcher.next_batch()
batch = Batcher.merge_batches(full_batch, partial_batch)
if batch.is_any_null():
print(partial_batch.original_abstracts_sents)
print(full_batch.original_abstracts_sents)
import ipdb
ipdb.set_trace()
print(np.concatenate((full_batch.original_abstracts_sents, partial_batch.original_abstracts_sents), axis=0))
raise Exception
else:
partial_batch = None
if FLAGS.ac_training:
t0 = time.time()
transitions = self.model.collect_dqn_transitions(sess, batch, train_step, batch.max_art_oovs) # len(batch_size * k * max_dec_steps)
tf.logging.info('Q values collection time: {}'.format(time.time()-t0))
with dqn_graph.as_default():
# if using true Q-value to train DQN network,
# we do this as the pre-training for the DQN network to get better estimates
batch_len = len(transitions)
b = ReplayBuffer.create_batch(self.dqn_hps, transitions,len(transitions), use_state_prime = True, max_art_oovs = batch.max_art_oovs)
b_prime = ReplayBuffer.create_batch(self.dqn_hps, transitions,len(transitions), use_state_prime = True, max_art_oovs = batch.max_art_oovs)
dqn_results = self.dqn.run_test_steps(sess=dqn_sess, x= b._x, return_best_action=True)
q_estimates = dqn_results['estimates'] # shape (len(transitions), vocab_size)
dqn_best_action = dqn_results['best_action']
tf.logging.info('running test step on dqn_target')
dqn_target_results = self.dqn_target.run_test_steps(dqn_sess, x= b_prime._x)
q_vals_new_t = dqn_target_results['estimates'] # shape (len(transitions), vocab_size)
# we need to expand the q_estimates to match the input batch max_art_oov
q_estimates = np.concatenate([q_estimates,np.zeros((len(transitions),batch.max_art_oovs))],axis=-1)
tf.logging.info('fixing the action q-estimates')
for i, tr in enumerate(transitions):
if tr.done:
q_estimates[i][tr.action] = tr.reward
else:
q_estimates[i][tr.action] = tr.reward + FLAGS.gamma * q_vals_new_t[i][dqn_best_action[i]]
if FLAGS.dqn_scheduled_sampling:
tf.logging.info('scheduled sampling on q-estimates')
q_estimates = self.scheduled_sampling(batch_len, FLAGS.sampling_probability, b._y_extended, q_estimates)
if not FLAGS.calculate_true_q:
# when we are not training DQN based on true Q-values
# we need to update Q-values in our transitions based on this q_estimates we collected from DQN current network.
for trans, q_val in zip(transitions,q_estimates):
trans.q_values = q_val # each have the size vocab_extended
q_estimates = np.reshape(q_estimates, [FLAGS.batch_size, FLAGS.k, FLAGS.max_dec_steps, -1]) # shape (batch_size, k, max_dec_steps, vocab_size_extended)
tf.logging.info('run eval step on seq2seq model.')
t0=time.time()
results = self.model.run_eval_steps(sess, batch, train_step, q_estimates)
t1=time.time()
else:
tf.logging.info('run eval step on seq2seq model.')
t0=time.time()
results = self.model.run_eval_steps(sess, batch, train_step)
t1=time.time()
tf.logging.info('experiment: {}'.format(FLAGS.exp_name))
tf.logging.info('processed_batch: {}, seconds for batch: {}'.format(processed_batch, t1-t0))
printer_helper = {}
loss = printer_helper['pgen_loss']= results['pgen_loss']
printer_helper['rl_full_reward_sampled'] = np.mean(results['full_ssr'])
printer_helper['rl_full_reward_greedy'] = np.mean(results['full_gsr'])
printer_helper['rl_full_reward_diff'] = results['full_reward_diff']
if FLAGS.rl_training:
loss = np.mean([results['full_rl_avg_logprobs'], results['partial_rl_avg_logprobs']])
printer_helper['shared_loss'] = results['shared_loss']
printer_helper['rl_full_loss'] = results['full_rl_loss']
printer_helper['rl_full_avg_logprobs'] = results['full_rl_avg_logprobs']
printer_helper['rl_partial_loss'] = results['partial_rl_loss']
printer_helper['rl_partial_avg_logprobs'] = results['partial_rl_avg_logprobs']
printer_helper['rl_partial_reward_sampled'] = results['partial_ssr']
printer_helper['rl_partial_reward_greedy'] = results['partial_gsr']
printer_helper['rl_partial_reward_diff'] = results['partial_reward_diff']
if FLAGS.coverage:
loss = printer_helper['coverage_loss'] = results['coverage_loss']
if FLAGS.rl_training or FLAGS.ac_training:
loss = printer_helper['rl_cov_total_loss'] = results['reinforce_cov_total_loss']
elif FLAGS.pointer_gen:
loss = printer_helper['pointer_cov_total_loss'] = results['pointer_cov_total_loss']
if FLAGS.rl_training:
greedy_rouges.append(np.mean([results['full_gsr'],results['partial_gsr']]))
sampled_rouges.append(np.mean([results['full_ssr'],results['partial_ssr']]))
else:
greedy_rouges.append(np.mean(results['full_gsr']))
sampled_rouges.append(np.mean(results['full_ssr']))
for (k,v) in sorted(printer_helper.items(), key=lambda x: x[0]):
if not np.isfinite(v):
raise Exception("{} is not finite. Stopping.".format(k))
tf.logging.info('{}: {}\t'.format(k,v))
tf.logging.info('-------------------------------------------')
time.sleep(2)
# add summaries
summaries = results['summaries']
train_step = results['global_step']
self.summary_writer.add_summary(summaries, train_step)
# calculate running avg loss
avg_losses.append(self.calc_running_avg_loss(np.asscalar(loss), running_avg_loss))
tf.logging.info('-------------------------------------------')
time.sleep(2)
running_avg_loss = np.mean(avg_losses)
running_greedy_rouge = np.mean(greedy_rouges)
running_sampled_rouge = np.mean(sampled_rouges)
self.summary_writer.add_summary(
tf.Summary(value=[tf.Summary.Value(tag="running_greedy_rouge", simple_value=running_greedy_rouge), ]),
train_step)
self.summary_writer.add_summary(
tf.Summary(value=[tf.Summary.Value(tag="running_sampled_rouge", simple_value=running_sampled_rouge), ]),
train_step)
self.summary_writer.add_summary(tf.Summary(
value=[tf.Summary.Value(tag='running_avg_loss/decay=%f' % (decay), simple_value=running_avg_loss), ]),
train_step)
tf.logging.info('==========================================')
tf.logging.info('best_loss: {}\trunning_avg_loss: {}\t'.format(best_loss, running_avg_loss))
tf.logging.info('greedy rouges: {}\tsampled rouges: {}\t'.format(running_greedy_rouge, running_sampled_rouge))
tf.logging.info('==========================================')
# If running_avg_loss is best so far, save this checkpoint (early stopping).
# These checkpoints will appear as bestmodel-<iteration_number> in the eval dir
if (best_loss is None) or (FLAGS.rouge_based_eval and running_greedy_rouge > best_loss) or (
not FLAGS.rouge_based_eval and running_avg_loss < best_loss):
tf.logging.info('Found new best model with %.3f %s. Saving to %s',
running_greedy_rouge if FLAGS.rouge_based_eval else running_avg_loss,
"running_greedy_rouge" if FLAGS.rouge_based_eval else "running_avg_loss",
bestmodel_save_path)
saver.save(sess, bestmodel_save_path, global_step=train_step, latest_filename='checkpoint_best')
best_loss = running_greedy_rouge if FLAGS.rouge_based_eval else running_avg_loss
time.sleep(15)
# flush the summary writer every so often
if train_step % 100 == 0:
self.summary_writer.flush()
def run_eval(self):
"""Repeatedly runs eval iterations, logging to screen and writing summaries. Saves the model with the best loss seen so far."""
self.model.build_graph() # build the graph
saver = tf.train.Saver(max_to_keep=3) # we will keep 3 best checkpoints at a time
sess = tf.Session(config=util.get_config())
if FLAGS.embedding:
sess.run(tf.global_variables_initializer(),feed_dict={self.model.embedding_place:self.word_vector})
eval_dir = os.path.join(FLAGS.log_root, "eval") # make a subdir of the root dir for eval data
bestmodel_save_path = os.path.join(eval_dir, 'bestmodel') # this is where checkpoints of best models are saved
self.summary_writer = tf.summary.FileWriter(eval_dir)
if FLAGS.ac_training:
tf.logging.info('DDQN building graph')
t1 = time.time()
dqn_graph = tf.Graph()
with dqn_graph.as_default():
self.dqn.build_graph() # build dqn graph
tf.logging.info('building current network took {} seconds'.format(time.time()-t1))
self.dqn_target.build_graph() # build dqn target graph
tf.logging.info('building target network took {} seconds'.format(time.time()-t1))
dqn_saver = tf.train.Saver(max_to_keep=3) # keep 3 checkpoints at a time
dqn_sess = tf.Session(config=util.get_config())
dqn_train_step = 0
replay_buffer = ReplayBuffer(self.dqn_hps)
running_avg_loss = 0 # the eval job keeps a smoother, running average loss to tell it when to implement early stopping
best_loss = self.restore_best_eval_model() # will hold the best loss achieved so far
train_step = 0
while True:
_ = util.load_ckpt(saver, sess) # load a new checkpoint
if FLAGS.ac_training:
_ = util.load_dqn_ckpt(dqn_saver, dqn_sess) # load a new checkpoint
processed_batch = 0
avg_losses = []
# evaluate for 100 * batch_size before comparing the loss
# we do this due to memory constraint, best to run eval on different machines with large batch size
while processed_batch < 100*FLAGS.batch_size:
processed_batch += FLAGS.batch_size
batch = self.batcher.next_batch() # get the next batch
if FLAGS.ac_training:
t0 = time.time()
transitions = self.model.collect_dqn_transitions(sess, batch, train_step, batch.max_art_oovs) # len(batch_size * k * max_dec_steps)
tf.logging.info('Q values collection time: {}'.format(time.time()-t0))
with dqn_graph.as_default():
# if using true Q-value to train DQN network,
# we do this as the pre-training for the DQN network to get better estimates
batch_len = len(transitions)
b = ReplayBuffer.create_batch(self.dqn_hps, transitions,len(transitions), use_state_prime = True, max_art_oovs = batch.max_art_oovs)
b_prime = ReplayBuffer.create_batch(self.dqn_hps, transitions,len(transitions), use_state_prime = True, max_art_oovs = batch.max_art_oovs)
dqn_results = self.dqn.run_test_steps(sess=dqn_sess, x= b._x, return_best_action=True)
q_estimates = dqn_results['estimates'] # shape (len(transitions), vocab_size)
dqn_best_action = dqn_results['best_action']
tf.logging.info('running test step on dqn_target')
dqn_target_results = self.dqn_target.run_test_steps(dqn_sess, x= b_prime._x)
q_vals_new_t = dqn_target_results['estimates'] # shape (len(transitions), vocab_size)
# we need to expand the q_estimates to match the input batch max_art_oov
q_estimates = np.concatenate([q_estimates,np.zeros((len(transitions),batch.max_art_oovs))],axis=-1)
tf.logging.info('fixing the action q-estimates')
for i, tr in enumerate(transitions):
if tr.done:
q_estimates[i][tr.action] = tr.reward
else:
q_estimates[i][tr.action] = tr.reward + FLAGS.gamma * q_vals_new_t[i][dqn_best_action[i]]
if FLAGS.dqn_scheduled_sampling:
tf.logging.info('scheduled sampling on q-estimates')
q_estimates = self.scheduled_sampling(batch_len, FLAGS.sampling_probability, b._y_extended, q_estimates)
if not FLAGS.calculate_true_q:
# when we are not training DQN based on true Q-values
# we need to update Q-values in our transitions based on this q_estimates we collected from DQN current network.
for trans, q_val in zip(transitions,q_estimates):
trans.q_values = q_val # each have the size vocab_extended
q_estimates = np.reshape(q_estimates, [FLAGS.batch_size, FLAGS.k, FLAGS.max_dec_steps, -1]) # shape (batch_size, k, max_dec_steps, vocab_size_extended)
tf.logging.info('run eval step on seq2seq model.')
t0=time.time()
results = self.model.run_eval_step(sess, batch, train_step, q_estimates)
t1=time.time()
else:
tf.logging.info('run eval step on seq2seq model.')
t0=time.time()
results = self.model.run_eval_step(sess, batch, train_step)
t1=time.time()
tf.logging.info('experiment: {}'.format(FLAGS.exp_name))
tf.logging.info('processed_batch: {}, seconds for batch: {}'.format(processed_batch, t1-t0))
printer_helper = {}
loss = printer_helper['pgen_loss']= results['pgen_loss']
if FLAGS.coverage:
printer_helper['coverage_loss'] = results['coverage_loss']
if FLAGS.rl_training or FLAGS.ac_training:
printer_helper['rl_cov_total_loss']= results['reinforce_cov_total_loss']
loss = printer_helper['pointer_cov_total_loss'] = results['pointer_cov_total_loss']
if FLAGS.rl_training or FLAGS.ac_training:
printer_helper['shared_loss'] = results['shared_loss']
printer_helper['rl_loss'] = results['rl_loss']
printer_helper['rl_avg_logprobs'] = results['rl_avg_logprobs']
if FLAGS.rl_training:
printer_helper['sampled_r'] = np.mean(results['sampled_sentence_r_values'])
printer_helper['greedy_r'] = np.mean(results['greedy_sentence_r_values'])
printer_helper['r_diff'] = printer_helper['greedy_r'] - printer_helper['sampled_r']
if FLAGS.ac_training:
printer_helper['dqn_loss'] = np.mean(self.avg_dqn_loss) if len(self.avg_dqn_loss) > 0 else 0
for (k,v) in printer_helper.items():
if not np.isfinite(v):
raise Exception("{} is not finite. Stopping.".format(k))
tf.logging.info('{}: {}\t'.format(k,v))
# add summaries
summaries = results['summaries']
train_step = results['global_step']
self.summary_writer.add_summary(summaries, train_step)
# calculate running avg loss
avg_losses.append(self.calc_running_avg_loss(np.asscalar(loss), running_avg_loss, train_step))
tf.logging.info('-------------------------------------------')
running_avg_loss = np.mean(avg_losses)
tf.logging.info('==========================================')
tf.logging.info('best_loss: {}\trunning_avg_loss: {}\t'.format(best_loss, running_avg_loss))
tf.logging.info('==========================================')
# If running_avg_loss is best so far, save this checkpoint (early stopping).
# These checkpoints will appear as bestmodel-<iteration_number> in the eval dir
if best_loss is None or running_avg_loss < best_loss:
tf.logging.info('Found new best model with %.3f running_avg_loss. Saving to %s', running_avg_loss, bestmodel_save_path)
saver.save(sess, bestmodel_save_path, global_step=train_step, latest_filename='checkpoint_best')
best_loss = running_avg_loss
# flush the summary writer every so often
if train_step % 100 == 0:
self.summary_writer.flush()
def run_training(self):
"""Repeatedly runs training iterations, logging loss to screen and writing summaries"""
tf.logging.info("Starting run_training")
if FLAGS.debug: # start the tensorflow debugger
self.sess = tf_debug.LocalCLIDebugWrapperSession(self.sess)
self.sess.add_tensor_filter("has_inf_or_nan", tf_debug.has_inf_or_nan)
self.train_step = 0
if FLAGS.ac_training:
# DDQN training is done asynchronously along with model training
tf.logging.info('Starting DQN training thread...')
self.dqn_train_step = 0
self.thrd_dqn_training = Thread(target=self.dqn_training)
self.thrd_dqn_training.daemon = True
self.thrd_dqn_training.start()
watcher = Thread(target=self.watch_threads)
watcher.daemon = True
watcher.start()
# starting the main thread
tf.logging.info('Starting Seq2Seq training...')
while True: # repeats until interrupted
batch = self.batcher.next_batch()
t0=time.time()
if FLAGS.ac_training:
# For DDQN, we first collect the model output to calculate the reward and Q-estimates
# Then we fix the estimation either using our target network or using the true Q-values
# This process will usually take time and we are working on improving it.
transitions = self.model.collect_dqn_transitions(self.sess, batch, self.train_step, batch.max_art_oovs) # len(batch_size * k * max_dec_steps)
tf.logging.info('Q-values collection time: {}'.format(time.time()-t0))
# whenever we are working with the DDQN, we switch using DDQN graph rather than default graph
with self.dqn_graph.as_default():
batch_len = len(transitions)
# we use current decoder state to predict q_estimates, use_state_prime = False
b = ReplayBuffer.create_batch(self.dqn_hps, transitions,len(transitions), use_state_prime = False, max_art_oovs = batch.max_art_oovs)
# we also get the next decoder state to correct the estimation, use_state_prime = True
b_prime = ReplayBuffer.create_batch(self.dqn_hps, transitions,len(transitions), use_state_prime = True, max_art_oovs = batch.max_art_oovs)
# use current DQN to estimate values from current decoder state
dqn_results = self.dqn.run_test_steps(sess=self.dqn_sess, x= b._x, return_best_action=True)
q_estimates = dqn_results['estimates'] # shape (len(transitions), vocab_size)
dqn_best_action = dqn_results['best_action']
#dqn_q_estimate_loss = dqn_results['loss']
# use target DQN to estimate values for the next decoder state
dqn_target_results = self.dqn_target.run_test_steps(self.dqn_sess, x= b_prime._x)
q_vals_new_t = dqn_target_results['estimates'] # shape (len(transitions), vocab_size)
# we need to expand the q_estimates to match the input batch max_art_oov
# we use the q_estimate of UNK token for all the OOV tokens
q_estimates = np.concatenate([q_estimates,
np.reshape(q_estimates[:,0],[-1,1])*np.ones((len(transitions),batch.max_art_oovs))],axis=-1)
# modify Q-estimates using the result collected from current and target DQN.
# check algorithm 5 in the paper for more info: https://arxiv.org/pdf/1805.09461.pdf
for i, tr in enumerate(transitions):
if tr.done:
q_estimates[i][tr.action] = tr.reward
else:
q_estimates[i][tr.action] = tr.reward + FLAGS.gamma * q_vals_new_t[i][dqn_best_action[i]]
# use scheduled sampling to whether use true Q-values or DDQN estimation
if FLAGS.dqn_scheduled_sampling:
q_estimates = self.scheduled_sampling(batch_len, FLAGS.sampling_probability, b._y_extended, q_estimates)
if not FLAGS.calculate_true_q:
# when we are not training DDQN based on true Q-values,
# we need to update Q-values in our transitions based on the q_estimates we collected from DQN current network.
for trans, q_val in zip(transitions,q_estimates):
trans.q_values = q_val # each have the size vocab_extended
q_estimates = np.reshape(q_estimates, [FLAGS.batch_size, FLAGS.k, FLAGS.max_dec_steps, -1]) # shape (batch_size, k, max_dec_steps, vocab_size_extended)
# Once we are done with modifying Q-values, we can use them to train the DDQN model.
# In this paper, we use a priority experience buffer which always selects states with higher quality
# to train the DDQN. The following line will add batch_size * max_dec_steps experiences to the replay buffer.
# As mentioned before, the DDQN training is asynchronous. Therefore, once the related queues for DDQN training
# are full, the DDQN will start the training.
self.replay_buffer.add(transitions)
# If dqn_pretrain flag is on, it means that we use a fixed Actor to only collect experiences for
# DDQN pre-training
if FLAGS.dqn_pretrain:
tf.logging.info('RUNNNING DQN PRETRAIN: Adding data to relplay buffer only...')
continue
# if not, use the q_estimation to update the loss.
results = self.model.run_train_steps(self.sess, batch, self.train_step, q_estimates)
else:
results = self.model.run_train_steps(self.sess, batch, self.train_step)
t1=time.time()
# get the summaries and iteration number so we can write summaries to tensorboard
summaries = results['summaries'] # we will write these summaries to tensorboard using summary_writer
self.train_step = results['global_step'] # we need this to update our running average loss
tf.logging.info('seconds for training step {}: {}'.format(self.train_step, t1-t0))
printer_helper = {}
printer_helper['pgen_loss']= results['pgen_loss']
if FLAGS.coverage:
printer_helper['coverage_loss'] = results['coverage_loss']
if FLAGS.rl_training or FLAGS.ac_training:
printer_helper['rl_cov_total_loss']= results['reinforce_cov_total_loss']
else:
printer_helper['pointer_cov_total_loss'] = results['pointer_cov_total_loss']
if FLAGS.rl_training or FLAGS.ac_training:
printer_helper['shared_loss'] = results['shared_loss']
printer_helper['rl_loss'] = results['rl_loss']
printer_helper['rl_avg_logprobs'] = results['rl_avg_logprobs']
if FLAGS.rl_training:
printer_helper['sampled_r'] = np.mean(results['sampled_sentence_r_values'])
printer_helper['greedy_r'] = np.mean(results['greedy_sentence_r_values'])
printer_helper['r_diff'] = printer_helper['sampled_r'] - printer_helper['greedy_r']
if FLAGS.ac_training:
printer_helper['dqn_loss'] = np.mean(self.avg_dqn_loss) if len(self.avg_dqn_loss)>0 else 0
for (k,v) in printer_helper.items():
if not np.isfinite(v):
raise Exception("{} is not finite. Stopping.".format(k))
tf.logging.info('{}: {}\t'.format(k,v))
tf.logging.info('-------------------------------------------')
self.summary_writer.add_summary(summaries, self.train_step) # write the summaries
if self.train_step % 100 == 0: # flush the summary writer every so often
self.summary_writer.flush()
if FLAGS.ac_training:
self.dqn_summary_writer.flush()
if self.train_step > FLAGS.max_iter: break
def run_training(self):
"""Repeatedly runs training iterations, logging loss to screen and writing summaries"""
tf.logging.info("Starting run_training")
if FLAGS.debug: # start the tensorflow debugger
self.sess = tf_debug.LocalCLIDebugWrapperSession(self.sess)
self.sess.add_tensor_filter("has_inf_or_nan", tf_debug.has_inf_or_nan)
self.train_step = 0
if FLAGS.ac_training:
# DDQN training is done asynchronously along with model training
tf.logging.info('Starting DQN training thread...')
self.dqn_train_step = 0
self.thrd_dqn_training = Thread(target=self.dqn_training)
self.thrd_dqn_training.daemon = True
self.thrd_dqn_training.start()
watcher = Thread(target=self.watch_threads)
watcher.daemon = True
watcher.start()
# starting the main thread
tf.logging.info('Starting Seq2Seq training...')
while True: # repeats until interrupted
batch = self.batcher.next_batch()
t0=time.time()
if FLAGS.ac_training:
# For DDQN, we first collect the model output to calculate the reward and Q-estimates
# Then we fix the estimation either using our target network or using the true Q-values
# This process will usually take time and we are working on improving it.
transitions = self.model.collect_dqn_transitions(self.sess, batch, self.train_step, batch.max_art_oovs) # len(batch_size * k * max_dec_steps)
tf.logging.info('Q-values collection time: {}'.format(time.time()-t0))
# whenever we are working with the DDQN, we switch using DDQN graph rather than default graph
with self.dqn_graph.as_default():
batch_len = len(transitions)
# we use current decoder state to predict q_estimates, use_state_prime = False
b = ReplayBuffer.create_batch(self.dqn_hps, transitions,len(transitions), use_state_prime = False, max_art_oovs = batch.max_art_oovs)
# we also get the next decoder state to correct the estimation, use_state_prime = True
b_prime = ReplayBuffer.create_batch(self.dqn_hps, transitions,len(transitions), use_state_prime = True, max_art_oovs = batch.max_art_oovs)
# use current DQN to estimate values from current decoder state
dqn_results = self.dqn.run_test_steps(sess=self.dqn_sess, x= b._x, return_best_action=True)
q_estimates = dqn_results['estimates'] # shape (len(transitions), vocab_size)
dqn_best_action = dqn_results['best_action']
#dqn_q_estimate_loss = dqn_results['loss']
# use target DQN to estimate values for the next decoder state
dqn_target_results = self.dqn_target.run_test_steps(self.dqn_sess, x= b_prime._x)
q_vals_new_t = dqn_target_results['estimates'] # shape (len(transitions), vocab_size)
# we need to expand the q_estimates to match the input batch max_art_oov
# we use the q_estimate of UNK token for all the OOV tokens
q_estimates = np.concatenate([q_estimates,
np.reshape(q_estimates[:,0],[-1,1])*np.ones((len(transitions),batch.max_art_oovs))],axis=-1)
# modify Q-estimates using the result collected from current and target DQN.
# check algorithm 5 in the paper for more info: https://arxiv.org/pdf/1805.09461.pdf
for i, tr in enumerate(transitions):
if tr.done:
q_estimates[i][tr.action] = tr.reward
else:
q_estimates[i][tr.action] = tr.reward + FLAGS.gamma * q_vals_new_t[i][dqn_best_action[i]]
# use scheduled sampling to whether use true Q-values or DDQN estimation
if FLAGS.dqn_scheduled_sampling:
q_estimates = self.scheduled_sampling(batch_len, FLAGS.sampling_probability, b._y_extended, q_estimates)
if not FLAGS.calculate_true_q:
# when we are not training DDQN based on true Q-values,
# we need to update Q-values in our transitions based on the q_estimates we collected from DQN current network.
for trans, q_val in zip(transitions,q_estimates):
trans.q_values = q_val # each have the size vocab_extended
q_estimates = np.reshape(q_estimates, [FLAGS.batch_size, FLAGS.k, FLAGS.max_dec_steps, -1]) # shape (batch_size, k, max_dec_steps, vocab_size_extended)
# Once we are done with modifying Q-values, we can use them to train the DDQN model.
# In this paper, we use a priority experience buffer which always selects states with higher quality
# to train the DDQN. The following line will add batch_size * max_dec_steps experiences to the replay buffer.
# As mentioned before, the DDQN training is asynchronous. Therefore, once the related queues for DDQN training
# are full, the DDQN will start the training.
self.replay_buffer.add(transitions)
# If dqn_pretrain flag is on, it means that we use a fixed Actor to only collect experiences for
# DDQN pre-training
if FLAGS.dqn_pretrain:
tf.logging.info('RUNNNING DQN PRETRAIN: Adding data to relplay buffer only...')
continue
# if not, use the q_estimation to update the loss.
results = self.model.run_train_steps(self.sess, batch, self.train_step, q_estimates)
else:
results = self.model.run_train_steps(self.sess, batch, self.train_step)
t1=time.time()
# get the summaries and iteration number so we can write summaries to tensorboard
summaries = results['summaries'] # we will write these summaries to tensorboard using summary_writer
self.train_step = results['global_step'] # we need this to update our running average loss
tf.logging.info('seconds for training step {}: {}'.format(self.train_step, t1-t0))
printer_helper = {}
printer_helper['pgen_loss']= results['pgen_loss']
if FLAGS.coverage:
printer_helper['coverage_loss'] = results['coverage_loss']
if FLAGS.rl_training or FLAGS.ac_training:
printer_helper['rl_cov_total_loss']= results['reinforce_cov_total_loss']
else:
printer_helper['pointer_cov_total_loss'] = results['pointer_cov_total_loss']
if FLAGS.rl_training or FLAGS.ac_training:
printer_helper['shared_loss'] = results['shared_loss']
printer_helper['rl_loss'] = results['rl_loss']
printer_helper['rl_avg_logprobs'] = results['rl_avg_logprobs']
if FLAGS.rl_training:
printer_helper['sampled_r'] = np.mean(results['sampled_sentence_r_values'])
printer_helper['greedy_r'] = np.mean(results['greedy_sentence_r_values'])
printer_helper['r_diff'] = printer_helper['greedy_r'] - printer_helper['sampled_r']
if FLAGS.ac_training:
printer_helper['dqn_loss'] = np.mean(self.avg_dqn_loss) if len(self.avg_dqn_loss)>0 else 0
for (k,v) in printer_helper.items():
if not np.isfinite(v):
raise Exception("{} is not finite. Stopping.".format(k))
tf.logging.info('{}: {}\t'.format(k,v))
tf.logging.info('-------------------------------------------')
self.summary_writer.add_summary(summaries, self.train_step) # write the summaries
if self.train_step % 100 == 0: # flush the summary writer every so often
self.summary_writer.flush()
if FLAGS.ac_training:
self.dqn_summary_writer.flush()
if self.train_step > FLAGS.max_iter: break
def run_training(self):
"""Repeatedly runs training iterations, logging loss to screen and writing summaries"""
tf.logging.info("Starting run_training")
if FLAGS.debug: # start the tensorflow debugger
self.sess = tf_debug.LocalCLIDebugWrapperSession(self.sess)
self.sess.add_tensor_filter("has_inf_or_nan",
tf_debug.has_inf_or_nan)
self.train_step = 0
if FLAGS.ac_training:
tf.logging.info('Starting DQN training thread...')
self.dqn_train_step = 0
self.thrd_dqn_training = Thread(target=self.dqn_training)
self.thrd_dqn_training.daemon = True
self.thrd_dqn_training.start()
watcher = Thread(target=self.watch_threads)
watcher.daemon = True
watcher.start()
tf.logging.info('Starting Seq2Seq training...')
while True: # repeats until interrupted
batch = self.batcher.next_batch()
t0 = time.time()
if FLAGS.ac_training:
transitions = self.model.collect_dqn_transitions(
self.sess, batch, self.train_step,
batch.max_art_oovs) # len(batch_size * k * max_dec_steps)
tf.logging.info(
'Q-values collection time: {}'.format(time.time() - t0))
with self.dqn_graph.as_default():
# if using true Q-value to train DQN network,
# we do this as the pre-training for the DQN network to get better estimates
batch_len = len(transitions)
b = ReplayBuffer.create_batch(
self.dqn_hps,
transitions,
len(transitions),
use_state_prime=True,
max_art_oovs=batch.max_art_oovs)
b_prime = ReplayBuffer.create_batch(
self.dqn_hps,
transitions,
len(transitions),
use_state_prime=True,
max_art_oovs=batch.max_art_oovs)
dqn_results = self.dqn.run_test_steps(
sess=self.dqn_sess, x=b._x, return_best_action=True)
q_estimates = dqn_results[
'estimates'] # shape (len(transitions), vocab_size)
dqn_best_action = dqn_results['best_action']
#dqn_q_estimate_loss = dqn_results['loss']
dqn_target_results = self.dqn_target.run_test_steps(
self.dqn_sess, x=b_prime._x)
q_vals_new_t = dqn_target_results[
'estimates'] # shape (len(transitions), vocab_size)
# we need to expand the q_estimates to match the input batch max_art_oov
q_estimates = np.concatenate([
q_estimates,
np.zeros((len(transitions), batch.max_art_oovs))
],
axis=-1)
for i, tr in enumerate(transitions):
if tr.done:
q_estimates[i][tr.action] = tr.reward
else:
q_estimates[i][
tr.
action] = tr.reward + FLAGS.gamma * q_vals_new_t[
i][dqn_best_action[i]]
if FLAGS.dqn_scheduled_sampling:
q_estimates = self.scheduled_sampling(
batch_len, FLAGS.sampling_probability,
b._y_extended, q_estimates)
if not FLAGS.calculate_true_q:
# when we are not training DQN based on true Q-values
# we need to update Q-values in our transitions based on this q_estimates we collected from DQN current network.
for trans, q_val in zip(transitions, q_estimates):
trans.q_values = q_val # each have the size vocab_extended
q_estimates = np.reshape(
q_estimates,
[FLAGS.batch_size, FLAGS.k, FLAGS.max_dec_steps, -1]
) # shape (batch_size, k, max_dec_steps, vocab_size_extended)
self.replay_buffer.add(transitions)
# if using estimated Q-value to train DQN network
# this way, we only need to calculate the reward for a single action, not the whole vocabulary
# we train the DQN network, based on q_estimate variable as the true Q-values
# therefore, we need to update true Q-value of the transitions variable with this one for each transition
# then finally add the updated transitions variable to replay buffer
if FLAGS.dqn_pretrain:
tf.logging.info(
'RUNNNING DQN PRETRAIN: Adding data to relplay buffer only...'
)
continue
results = self.model.run_train_steps(self.sess, batch,
self.train_step,
q_estimates)
else:
results = self.model.run_train_steps(self.sess, batch,
self.train_step)
t1 = time.time()
# get the summaries and iteration number so we can write summaries to tensorboard
summaries = results[
'summaries'] # we will write these summaries to tensorboard using summary_writer
self.train_step = results[
'global_step'] # we need this to update our running average loss
tf.logging.info('seconds for training step {}: {}'.format(
self.train_step, t1 - t0))
printer_helper = {}
printer_helper['pgen_loss'] = results['pgen_loss']
if FLAGS.coverage:
printer_helper['coverage_loss'] = results['coverage_loss']
if FLAGS.rl_training or FLAGS.ac_training:
printer_helper['rl_cov_total_loss'] = results[
'reinforce_cov_total_loss']
else:
printer_helper['pointer_cov_total_loss'] = results[
'pointer_cov_total_loss']
if FLAGS.rl_training or FLAGS.ac_training:
printer_helper['shared_loss'] = results['shared_loss']
printer_helper['rl_loss'] = results['rl_loss']
printer_helper['rl_avg_logprobs'] = results['rl_avg_logprobs']
if FLAGS.rl_training:
printer_helper['sampled_r'] = np.mean(
results['sampled_sentence_r_values'])
printer_helper['greedy_r'] = np.mean(
results['greedy_sentence_r_values'])
printer_helper['r_diff'] = printer_helper[
'sampled_r'] - printer_helper['greedy_r']
if FLAGS.ac_training:
printer_helper['dqn_loss'] = np.mean(
self.avg_dqn_loss) if len(self.avg_dqn_loss) > 0 else 0
for (k, v) in printer_helper.items():
if not np.isfinite(v):
raise Exception("{} is not finite. Stopping.".format(k))
tf.logging.info('{}: {}\t'.format(k, v))
tf.logging.info('-------------------------------------------')
self.summary_writer.add_summary(
summaries, self.train_step) # write the summaries
if self.train_step % 100 == 0: # flush the summary writer every so often
self.summary_writer.flush()
if FLAGS.ac_training:
self.dqn_summary_writer.flush()
if self.train_step > FLAGS.max_iter: break