def train(sess, loss, x, y, X_train, Y_train, save=False,
init_all=True, evaluate=None, feed=None, args=None,
rng=None, var_list=None, fprop_args=None, optimizer=None):
"""
Train a TF graph.
This function is not yet deprecated, but is likely to become deprecated
soon. Prefer cleverhans.train.train when possible.
cleverhans.train.train supports multiple GPUs but this function is still
needed to support legacy models that do not support calling fprop more
than once.
:param sess: TF session to use when training the graph
:param loss: tensor, the model training loss.
:param x: input placeholder
:param y: output placeholder (for labels)
:param X_train: numpy array with training inputs
:param Y_train: numpy array with training outputs
:param save: boolean controlling the save operation
:param init_all: (boolean) If set to true, all TF variables in the session
are (re)initialized, otherwise only previously
uninitialized variables are initialized before training.
:param evaluate: function that is run after each training iteration
(typically to display the test/validation accuracy).
:param feed: An optional dictionary that is appended to the feeding
dictionary before the session runs. Can be used to feed
the learning phase of a Keras model for instance.
:param args: dict or argparse `Namespace` object.
Should contain `nb_epochs`, `learning_rate`,
`batch_size`
If save is True, should also contain 'train_dir'
and 'filename'
:param rng: Instance of numpy.random.RandomState
:param var_list: Optional list of parameters to train.
:param fprop_args: dict, extra arguments to pass to fprop (loss and model).
:param optimizer: Optimizer to be used for training
:return: True if model trained
"""
args = _ArgsWrapper(args or {})
fprop_args = fprop_args or {}
# Check that necessary arguments were given (see doc above)
assert args.nb_epochs, "Number of epochs was not given in args dict"
if optimizer is None:
assert args.learning_rate is not None, ("Learning rate was not given "
"in args dict")
assert args.batch_size, "Batch size was not given in args dict"
if save:
assert args.train_dir, "Directory for save was not given in args dict"
assert args.filename, "Filename for save was not given in args dict"
if rng is None:
rng = np.random.RandomState()
# Define optimizer
loss_value = loss.fprop(x, y, **fprop_args)
if optimizer is None:
optimizer = tf.train.AdamOptimizer(learning_rate=args.learning_rate)
else:
if not isinstance(optimizer, tf.train.Optimizer):
raise ValueError("optimizer object must be from a child class of "
"tf.train.Optimizer")
# Trigger update operations within the default graph (such as batch_norm).
with tf.control_dependencies(tf.get_collection(tf.GraphKeys.UPDATE_OPS)):
train_step = optimizer.minimize(loss_value, var_list=var_list)
with sess.as_default():
if hasattr(tf, "global_variables_initializer"):
if init_all:
tf.global_variables_initializer().run()
else:
initialize_uninitialized_global_variables(sess)
else:
warnings.warn("Update your copy of tensorflow; future versions of "
"CleverHans may drop support for this version.")
sess.run(tf.initialize_all_variables())
for epoch in xrange(args.nb_epochs):
# Compute number of batches
nb_batches = int(math.ceil(float(len(X_train)) / args.batch_size))
assert nb_batches * args.batch_size >= len(X_train)
# Indices to shuffle training set
index_shuf = list(range(len(X_train)))
rng.shuffle(index_shuf)
prev = time.time()
for batch in range(nb_batches):
# Compute batch start and end indices
start, end = batch_indices(
batch, len(X_train), args.batch_size)
# Perform one training step
feed_dict = {x: X_train[index_shuf[start:end]],
y: Y_train[index_shuf[start:end]]}
if feed is not None:
feed_dict.update(feed)
train_step.run(feed_dict=feed_dict)
assert end >= len(X_train) # Check that all examples were used
cur = time.time()
_logger.info("Epoch " + str(epoch) + " took " +
str(cur - prev) + " seconds")
if evaluate is not None:
evaluate()
if save:
save_path = os.path.join(args.train_dir, args.filename)
saver = tf.train.Saver()
saver.save(sess, save_path)
_logger.info("Completed model training and saved at: " +
str(save_path))
else:
_logger.info("Completed model training.")
return True
def model_eval(sess, x, y, predictions, X_test=None, Y_test=None,
feed=None, args=None):
"""
Compute the accuracy of a TF model on some data
:param sess: TF session to use
:param x: input placeholder
:param y: output placeholder (for labels)
:param predictions: model output predictions
:param X_test: numpy array with training inputs
:param Y_test: numpy array with training outputs
:param feed: An optional dictionary that is appended to the feeding
dictionary before the session runs. Can be used to feed
the learning phase of a Keras model for instance.
:param args: dict or argparse `Namespace` object.
Should contain `batch_size`
:return: a float with the accuracy value
"""
args = _ArgsWrapper(args or {})
assert args.batch_size, "Batch size was not given in args dict"
if X_test is None or Y_test is None:
raise ValueError("X_test argument and Y_test argument "
"must be supplied.")
# Define accuracy symbolically
if LooseVersion(tf.__version__) >= LooseVersion('1.0.0'):
correct_preds = tf.equal(tf.argmax(y, axis=-1),
tf.argmax(predictions, axis=-1))
else:
correct_preds = tf.equal(tf.argmax(y, axis=tf.rank(y) - 1),
tf.argmax(predictions,
axis=tf.rank(predictions) - 1))
# Init result var
accuracy = 0.0
with sess.as_default():
# Compute number of batches
nb_batches = int(math.ceil(float(len(X_test)) / args.batch_size))
assert nb_batches * args.batch_size >= len(X_test)
X_cur = np.zeros((args.batch_size,) + X_test.shape[1:],
dtype=X_test.dtype)
Y_cur = np.zeros((args.batch_size,) + Y_test.shape[1:],
dtype=Y_test.dtype)
for batch in range(nb_batches):
if batch % 100 == 0 and batch > 0:
_logger.debug("Batch " + str(batch))
# Must not use the `batch_indices` function here, because it
# repeats some examples.
# It's acceptable to repeat during training, but not eval.
start = batch * args.batch_size
end = min(len(X_test), start + args.batch_size)
# The last batch may be smaller than all others. This should not
# affect the accuarcy disproportionately.
cur_batch_size = end - start
X_cur[:cur_batch_size] = X_test[start:end]
Y_cur[:cur_batch_size] = Y_test[start:end]
feed_dict = {x: X_cur, y: Y_cur}
if feed is not None:
feed_dict.update(feed)
cur_corr_preds = correct_preds.eval(feed_dict=feed_dict)
accuracy += cur_corr_preds[:cur_batch_size].sum()
assert end >= len(X_test)
# Divide by number of examples to get final value
accuracy /= len(X_test)
return accuracy
def model_train(sess, x, y, predictions, X_train, Y_train, save=False,
predictions_adv=None, init_all=True, evaluate=None,
feed=None, args=None, rng=None, var_list=None):
"""
Train a TF graph
:param sess: TF session to use when training the graph
:param x: input placeholder
:param y: output placeholder (for labels)
:param predictions: model output predictions
:param X_train: numpy array with training inputs
:param Y_train: numpy array with training outputs
:param save: boolean controlling the save operation
:param predictions_adv: if set with the adversarial example tensor,
will run adversarial training
:param init_all: (boolean) If set to true, all TF variables in the session
are (re)initialized, otherwise only previously
uninitialized variables are initialized before training.
:param evaluate: function that is run after each training iteration
(typically to display the test/validation accuracy).
:param feed: An optional dictionary that is appended to the feeding
dictionary before the session runs. Can be used to feed
the learning phase of a Keras model for instance.
:param args: dict or argparse `Namespace` object.
Should contain `nb_epochs`, `learning_rate`,
`batch_size`
If save is True, should also contain 'train_dir'
and 'filename'
:param rng: Instance of numpy.random.RandomState
:param var_list: Optional list of parameters to train.
:return: True if model trained
"""
warnings.warn('This function is deprecated.')
args = _ArgsWrapper(args or {})
# Check that necessary arguments were given (see doc above)
assert args.nb_epochs, "Number of epochs was not given in args dict"
assert args.learning_rate, "Learning rate was not given in args dict"
assert args.batch_size, "Batch size was not given in args dict"
if save:
assert args.train_dir, "Directory for save was not given in args dict"
assert args.filename, "Filename for save was not given in args dict"
if rng is None:
rng = np.random.RandomState()
# Define loss
loss = model_loss(y, predictions)
if predictions_adv is not None:
loss = (loss + model_loss(y, predictions_adv)) / 2
train_step = tf.train.AdamOptimizer(learning_rate=args.learning_rate)
train_step = train_step.minimize(loss, var_list=var_list)
with sess.as_default():
if hasattr(tf, "global_variables_initializer"):
if init_all:
tf.global_variables_initializer().run()
else:
initialize_uninitialized_global_variables(sess)
else:
warnings.warn("Update your copy of tensorflow; future versions of "
"CleverHans may drop support for this version.")
sess.run(tf.initialize_all_variables())
for epoch in xrange(args.nb_epochs):
# Compute number of batches
nb_batches = int(math.ceil(float(len(X_train)) / args.batch_size))
assert nb_batches * args.batch_size >= len(X_train)
# Indices to shuffle training set
index_shuf = list(range(len(X_train)))
rng.shuffle(index_shuf)
prev = time.time()
for batch in range(nb_batches):
# Compute batch start and end indices
start, end = batch_indices(
batch, len(X_train), args.batch_size)
# Perform one training step
feed_dict = {x: X_train[index_shuf[start:end]],
y: Y_train[index_shuf[start:end]]}
if feed is not None:
feed_dict.update(feed)
train_step.run(feed_dict=feed_dict)
assert end >= len(X_train) # Check that all examples were used
cur = time.time()
_logger.info("Epoch " + str(epoch) + " took " +
str(cur - prev) + " seconds")
if evaluate is not None:
evaluate()
if save:
save_path = os.path.join(args.train_dir, args.filename)
saver = tf.train.Saver()
saver.save(sess, save_path)
_logger.info("Completed model training and saved at: " +
str(save_path))
else:
_logger.info("Completed model training.")
return True
def train(sess,
loss,
x_train,
y_train,
init_all=True,
evaluate=None,
feed=None,
args=None,
rng=None,
var_list=None,
fprop_args=None,
optimizer=None,
devices=None,
x_batch_preprocessor=None,
use_ema=False,
ema_decay=.998,
run_canary=True,
loss_threshold=1e5):
"""
Run (optionally multi-replica, synchronous) training to minimize `loss`
:param sess: TF session to use when training the graph
:param loss: tensor, the loss to minimize
:param x_train: numpy array with training inputs
:param y_train: numpy array with training outputs
:param init_all: (boolean) If set to true, all TF variables in the session
are (re)initialized, otherwise only previously
uninitialized variables are initialized before training.
:param evaluate: function that is run after each training iteration
(typically to display the test/validation accuracy).
:param feed: An optional dictionary that is appended to the feeding
dictionary before the session runs. Can be used to feed
the learning phase of a Keras model for instance.
:param args: dict or argparse `Namespace` object.
Should contain `nb_epochs`, `learning_rate`,
`batch_size`
:param rng: Instance of numpy.random.RandomState
:param var_list: Optional list of parameters to train.
:param fprop_args: dict, extra arguments to pass to fprop (loss and model).
:param optimizer: Optimizer to be used for training
:param devices: list of device names to use for training
If None, defaults to: all GPUs, if GPUs are available
all devices, if no GPUs are available
:param x_batch_preprocessor: callable
Takes a single tensor containing an x_train batch as input
Returns a single tensor containing an x_train batch as output
Called to preprocess the data before passing the data to the Loss
:param use_ema: bool
If true, uses an exponential moving average of the model parameters
:param ema_decay: float or callable
The decay parameter for EMA, if EMA is used
If a callable rather than a float, this is a callable that takes
the epoch and batch as arguments and returns the ema_decay for
the current batch.
:param run_canary: bool
If True and using 3 or more GPUs, runs some canary code that should
fail if there is a multi-GPU driver problem.
Turn this off if your gradients are inherently stochastic (e.g.
if you use dropout). The canary code checks that all GPUs give
approximately the same gradient.
:param loss_threshold: float
Raise an exception if the loss exceeds this value.
This is intended to rapidly detect numerical problems.
Sometimes the loss may legitimately be higher than this value. In
such cases, raise the value. If needed it can be np.inf.
:return: True if model trained
"""
args = _ArgsWrapper(args or {})
fprop_args = fprop_args or {}
# Check that necessary arguments were given (see doc above)
assert args.nb_epochs, "Number of epochs was not given in args dict"
if optimizer is None:
if args.learning_rate is None:
raise ValueError("Learning rate was not given in args dict")
assert args.batch_size, "Batch size was not given in args dict"
if rng is None:
rng = np.random.RandomState()
if optimizer is None:
optimizer = tf.train.AdamOptimizer(learning_rate=args.learning_rate)
else:
if not isinstance(optimizer, tf.train.Optimizer):
raise ValueError("optimizer object must be from a child class of "
"tf.train.Optimizer")
grads = []
xs = []
preprocessed_xs = []
ys = []
devices = infer_devices(devices)
for idx, device in enumerate(devices):
with tf.device(device):
x = tf.placeholder(x_train.dtype, (None, ) + x_train.shape[1:])
y = tf.placeholder(x_train.dtype, (None, ) + y_train.shape[1:])
xs.append(x)
ys.append(y)
if x_batch_preprocessor is not None:
x = x_batch_preprocessor(x)
# We need to keep track of these so that the canary can feed
# preprocessed values. If the canary had to feed raw values,
# stochastic preprocessing could make the canary fail.
preprocessed_xs.append(x)
loss_value = loss.fprop(x, y, **fprop_args)
grads.append(
optimizer.compute_gradients(loss_value, var_list=var_list))
num_devices = len(devices)
print("num_devices: ", num_devices)
grad = avg_grads(grads)
# Trigger update operations within the default graph (such as batch_norm).
with tf.control_dependencies(tf.get_collection(tf.GraphKeys.UPDATE_OPS)):
train_step = optimizer.apply_gradients(grad)
epoch_tf = tf.placeholder(tf.int32, [])
batch_tf = tf.placeholder(tf.int32, [])
if use_ema:
if callable(ema_decay):
ema_decay = ema_decay(epoch_tf, batch_tf)
ema = tf.train.ExponentialMovingAverage(decay=ema_decay)
with tf.control_dependencies([train_step]):
train_step = ema.apply(var_list)
# Get pointers to the EMA's running average variables
avg_params = [ema.average(param) for param in var_list]
# Make temporary buffers used for swapping the live and running average
# parameters
tmp_params = [
tf.Variable(param, trainable=False) for param in var_list
]
# Define the swapping operation
param_to_tmp = [
tf.assign(tmp, param)
for tmp, param in safe_zip(tmp_params, var_list)
]
with tf.control_dependencies(param_to_tmp):
avg_to_param = [
tf.assign(param, avg)
for param, avg in safe_zip(var_list, avg_params)
]
with tf.control_dependencies(avg_to_param):
tmp_to_avg = [
tf.assign(avg, tmp)
for avg, tmp in safe_zip(avg_params, tmp_params)
]
swap = tmp_to_avg
batch_size = args.batch_size
assert batch_size % num_devices == 0
device_batch_size = batch_size // num_devices
if init_all:
sess.run(tf.global_variables_initializer())
else:
initialize_uninitialized_global_variables(sess)
# Check whether the hardware is working correctly
# So far the failure has only been observed with 3 or more GPUs
run_canary = run_canary and num_devices > 2
if run_canary:
canary_feed_dict = {}
for x, y in safe_zip(preprocessed_xs, ys):
canary_feed_dict[x] = x_train[:device_batch_size].copy()
canary_feed_dict[y] = y_train[:device_batch_size].copy()
# To reduce the runtime and memory cost of this canary,
# we test the gradient of only one parameter.
# For now this is just set to the first parameter in the list,
# because it is an index that is always guaranteed to work.
# If we think that this is causing false negatives and we should
# test other parameters, we could test a random parameter from
# the list or we could rewrite the canary to examine more than
# one parameter.
param_to_test = 0
grad_vars = []
for i in xrange(num_devices):
dev_grads = grads[i]
grad_vars.append(dev_grads[param_to_test][0])
grad_values = sess.run(grad_vars, feed_dict=canary_feed_dict)
failed = False
for i in xrange(1, num_devices):
if grad_values[0].shape != grad_values[i].shape:
print("shape 0 does not match shape %d:" % i,
grad_values[0].shape, grad_values[i].shape)
failed = True
continue
if not np.allclose(grad_values[0], grad_values[i], atol=1e-6):
print("grad_values[0]: ", grad_values[0].mean(),
grad_values[0].max())
print("grad_values[%d]: " % i, grad_values[i].mean(),
grad_values[i].max())
print("max diff: ",
np.abs(grad_values[0] - grad_values[1]).max())
failed = True
if failed:
print("Canary failed.")
quit()
for epoch in xrange(args.nb_epochs):
# Indices to shuffle training set
index_shuf = list(range(len(x_train)))
# Randomly repeat a few training examples each epoch to avoid
# having a too-small batch
while len(index_shuf) % batch_size != 0:
index_shuf.append(rng.randint(len(x_train)))
nb_batches = len(index_shuf) // batch_size
rng.shuffle(index_shuf)
# Shuffling here versus inside the loop doesn't seem to affect
# timing very much, but shuffling here makes the code slightly
# easier to read
x_train_shuffled = x_train[index_shuf]
y_train_shuffled = y_train[index_shuf]
prev = time.time()
for batch in range(nb_batches):
# Compute batch start and end indices
start = batch * batch_size
end = (batch + 1) * batch_size
# Perform one training step
feed_dict = {epoch_tf: epoch, batch_tf: batch}
diff = end - start
assert diff == batch_size
for dev_idx in xrange(num_devices):
cur_start = start + dev_idx * device_batch_size
cur_end = start + (dev_idx + 1) * device_batch_size
feed_dict[xs[dev_idx]] = x_train_shuffled[cur_start:cur_end]
feed_dict[ys[dev_idx]] = y_train_shuffled[cur_start:cur_end]
if cur_end != end:
msg = ("batch_size (%d) must be a multiple of num_devices "
"(%d).\nCUDA_VISIBLE_DEVICES: %s"
"\ndevices: %s")
args = (batch_size, num_devices,
os.environ['CUDA_VISIBLE_DEVICES'], str(devices))
raise ValueError(msg % args)
if feed is not None:
feed_dict.update(feed)
_, loss_numpy = sess.run([train_step, loss_value],
feed_dict=feed_dict)
if np.abs(loss_numpy) > loss_threshold:
raise ValueError("Extreme loss during training: ", loss_numpy)
if np.isnan(loss_numpy) or np.isinf(loss_numpy):
raise ValueError("NaN/Inf loss during training")
assert end == len(index_shuf) # Check that all examples were used
cur = time.time()
_logger.info("Epoch " + str(epoch) + " took " + str(cur - prev) +
" seconds")
if evaluate is not None:
if use_ema:
# Before running evaluation, load the running average
# parameters into the live slot, so we can see how well
# the EMA parameters are performing
sess.run(swap)
evaluate()
if use_ema:
# Swap the parameters back, so that we continue training
# on the live parameters
sess.run(swap)
if use_ema:
# When training is done, swap the running average parameters into
# the live slot, so that we use them when we deploy the model
sess.run(swap)
return True