forked from 626_privacy/tensorflow_privacy
Refactor MNIST tutorials and create new TPU tutorial:
1. Move common code to new file mnist_dpsgd_tutorial_common.py. 2. Move epsilon computation function out of binary into its own library. 3. Create new TPU tutorial. PiperOrigin-RevId: 310409308
This commit is contained in:
parent
164a57546a
commit
10335f6177
6 changed files with 351 additions and 156 deletions
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@ -32,18 +32,16 @@ from __future__ import absolute_import
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from __future__ import division
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from __future__ import print_function
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import math
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import sys
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from absl import app
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from absl import flags
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from tensorflow_privacy.privacy.analysis.compute_dp_sgd_privacy_lib import compute_dp_sgd_privacy
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# Opting out of loading all sibling packages and their dependencies.
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sys.skip_tf_privacy_import = True
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from tensorflow_privacy.privacy.analysis.rdp_accountant import compute_rdp # pylint: disable=g-import-not-at-top
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from tensorflow_privacy.privacy.analysis.rdp_accountant import get_privacy_spent
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FLAGS = flags.FLAGS
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flags.DEFINE_integer('N', None, 'Total number of examples')
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@ -53,42 +51,6 @@ flags.DEFINE_float('epochs', None, 'Number of epochs (may be fractional)')
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flags.DEFINE_float('delta', 1e-6, 'Target delta')
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def apply_dp_sgd_analysis(q, sigma, steps, orders, delta):
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"""Compute and print results of DP-SGD analysis."""
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# compute_rdp requires that sigma be the ratio of the standard deviation of
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# the Gaussian noise to the l2-sensitivity of the function to which it is
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# added. Hence, sigma here corresponds to the `noise_multiplier` parameter
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# in the DP-SGD implementation found in privacy.optimizers.dp_optimizer
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rdp = compute_rdp(q, sigma, steps, orders)
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eps, _, opt_order = get_privacy_spent(orders, rdp, target_delta=delta)
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print('DP-SGD with sampling rate = {:.3g}% and noise_multiplier = {} iterated'
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' over {} steps satisfies'.format(100 * q, sigma, steps), end=' ')
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print('differential privacy with eps = {:.3g} and delta = {}.'.format(
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eps, delta))
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print('The optimal RDP order is {}.'.format(opt_order))
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if opt_order == max(orders) or opt_order == min(orders):
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print('The privacy estimate is likely to be improved by expanding '
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'the set of orders.')
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return eps, opt_order
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def compute_dp_sgd_privacy(n, batch_size, noise_multiplier, epochs, delta):
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"""Compute epsilon based on the given hyperparameters."""
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q = batch_size / n # q - the sampling ratio.
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if q > 1:
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raise app.UsageError('n must be larger than the batch size.')
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orders = ([1.25, 1.5, 1.75, 2., 2.25, 2.5, 3., 3.5, 4., 4.5] +
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list(range(5, 64)) + [128, 256, 512])
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steps = int(math.ceil(epochs * n / batch_size))
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return apply_dp_sgd_analysis(q, noise_multiplier, steps, orders, delta)
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def main(argv):
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del argv # argv is not used.
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@ -0,0 +1,66 @@
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# Copyright 2019 The TensorFlow Authors. All Rights Reserved.
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#
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# Licensed under the Apache License, Version 2.0 (the "License");
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# you may not use this file except in compliance with the License.
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# You may obtain a copy of the License at
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#
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# http://www.apache.org/licenses/LICENSE-2.0
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#
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# Unless required by applicable law or agreed to in writing, software
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# distributed under the License is distributed on an "AS IS" BASIS,
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# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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# See the License for the specific language governing permissions and
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# limitations under the License.
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# ==============================================================================
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"""Library for computing privacy values for DP-SGD."""
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from __future__ import absolute_import
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from __future__ import division
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from __future__ import print_function
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import math
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import sys
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from absl import app
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# Opting out of loading all sibling packages and their dependencies.
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sys.skip_tf_privacy_import = True
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from tensorflow_privacy.privacy.analysis.rdp_accountant import compute_rdp # pylint: disable=g-import-not-at-top
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from tensorflow_privacy.privacy.analysis.rdp_accountant import get_privacy_spent
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def apply_dp_sgd_analysis(q, sigma, steps, orders, delta):
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"""Compute and print results of DP-SGD analysis."""
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# compute_rdp requires that sigma be the ratio of the standard deviation of
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# the Gaussian noise to the l2-sensitivity of the function to which it is
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# added. Hence, sigma here corresponds to the `noise_multiplier` parameter
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# in the DP-SGD implementation found in privacy.optimizers.dp_optimizer
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rdp = compute_rdp(q, sigma, steps, orders)
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eps, _, opt_order = get_privacy_spent(orders, rdp, target_delta=delta)
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print('DP-SGD with sampling rate = {:.3g}% and noise_multiplier = {} iterated'
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' over {} steps satisfies'.format(100 * q, sigma, steps), end=' ')
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print('differential privacy with eps = {:.3g} and delta = {}.'.format(
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eps, delta))
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print('The optimal RDP order is {}.'.format(opt_order))
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if opt_order == max(orders) or opt_order == min(orders):
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print('The privacy estimate is likely to be improved by expanding '
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'the set of orders.')
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return eps, opt_order
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def compute_dp_sgd_privacy(n, batch_size, noise_multiplier, epochs, delta):
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"""Compute epsilon based on the given hyperparameters."""
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q = batch_size / n # q - the sampling ratio.
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if q > 1:
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raise app.UsageError('n must be larger than the batch size.')
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orders = ([1.25, 1.5, 1.75, 2., 2.25, 2.5, 3., 3.5, 4., 4.5] +
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list(range(5, 64)) + [128, 256, 512])
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steps = int(math.ceil(epochs * n / batch_size))
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return apply_dp_sgd_analysis(q, noise_multiplier, steps, orders, delta)
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@ -20,7 +20,7 @@ from __future__ import print_function
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from absl.testing import absltest
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from absl.testing import parameterized
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from tensorflow_privacy.privacy.analysis import compute_dp_sgd_privacy
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from tensorflow_privacy.privacy.analysis import compute_dp_sgd_privacy_lib
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class ComputeDpSgdPrivacyTest(parameterized.TestCase):
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@ -32,7 +32,7 @@ class ComputeDpSgdPrivacyTest(parameterized.TestCase):
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)
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def test_compute_dp_sgd_privacy(self, n, batch_size, noise_multiplier, epochs,
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delta, expected_eps, expected_order):
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eps, order = compute_dp_sgd_privacy.compute_dp_sgd_privacy(
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eps, order = compute_dp_sgd_privacy_lib.compute_dp_sgd_privacy(
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n, batch_size, noise_multiplier, epochs, delta)
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self.assertAlmostEqual(eps, expected_eps)
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self.assertAlmostEqual(order, expected_order)
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@ -1,4 +1,4 @@
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# Copyright 2018, The TensorFlow Authors.
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# Copyright 2020, The TensorFlow Authors.
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#
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# Licensed under the Apache License, Version 2.0 (the "License");
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# you may not use this file except in compliance with the License.
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@ -12,26 +12,23 @@
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# See the License for the specific language governing permissions and
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# limitations under the License.
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"""Training a CNN on MNIST with differentially private SGD optimizer."""
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"""Train a CNN on MNIST with differentially private SGD optimizer."""
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from __future__ import absolute_import
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from __future__ import division
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from __future__ import print_function
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import time
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from absl import app
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from absl import flags
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from absl import logging
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import numpy as np
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import tensorflow.compat.v1 as tf
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from tensorflow_privacy.privacy.analysis import privacy_ledger
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from tensorflow_privacy.privacy.analysis.rdp_accountant import compute_rdp_from_ledger
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from tensorflow_privacy.privacy.analysis.rdp_accountant import get_privacy_spent
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from tensorflow_privacy.privacy.analysis import compute_dp_sgd_privacy_lib
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from tensorflow_privacy.privacy.optimizers import dp_optimizer
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GradientDescentOptimizer = tf.train.GradientDescentOptimizer
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FLAGS = flags.FLAGS
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from tensorflow_privacy.tutorials import mnist_dpsgd_tutorial_common as common
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flags.DEFINE_boolean(
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'dpsgd', True, 'If True, train with DP-SGD. If False, '
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@ -41,62 +38,20 @@ flags.DEFINE_float('noise_multiplier', 1.1,
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'Ratio of the standard deviation to the clipping norm')
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flags.DEFINE_float('l2_norm_clip', 1.0, 'Clipping norm')
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flags.DEFINE_integer('batch_size', 256, 'Batch size')
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flags.DEFINE_integer('epochs', 60, 'Number of epochs')
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flags.DEFINE_integer('epochs', 30, 'Number of epochs')
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flags.DEFINE_integer(
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'microbatches', 256, 'Number of microbatches '
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'(must evenly divide batch_size)')
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flags.DEFINE_string('model_dir', None, 'Model directory')
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class EpsilonPrintingTrainingHook(tf.estimator.SessionRunHook):
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"""Training hook to print current value of epsilon after an epoch."""
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def __init__(self, ledger):
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"""Initalizes the EpsilonPrintingTrainingHook.
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Args:
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ledger: The privacy ledger.
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"""
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self._samples, self._queries = ledger.get_unformatted_ledger()
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def end(self, session):
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# Any RDP order (for order > 1) corresponds to one epsilon value. We
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# enumerate through a few orders and pick the one that gives lowest epsilon.
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# The variable orders may be extended for different use cases. Usually, the
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# search is set to be finer-grained for small orders and coarser-grained for
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# larger orders.
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orders = [1 + x / 10.0 for x in range(1, 100)] + list(range(12, 64))
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samples = session.run(self._samples)
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queries = session.run(self._queries)
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formatted_ledger = privacy_ledger.format_ledger(samples, queries)
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rdp = compute_rdp_from_ledger(formatted_ledger, orders)
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# It is recommended that delta is o(1/dataset_size). In the case of MNIST,
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# dataset_size is 60000, so we set delta to be 1e-5. For larger datasets,
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# delta should be set smaller.
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eps = get_privacy_spent(orders, rdp, target_delta=1e-5)[0]
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print('For delta=1e-5, the current epsilon is: %.2f' % eps)
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FLAGS = flags.FLAGS
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def cnn_model_fn(features, labels, mode):
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def cnn_model_fn(features, labels, mode, params): # pylint: disable=unused-argument
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"""Model function for a CNN."""
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# Define CNN architecture using tf.keras.layers.
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input_layer = tf.reshape(features['x'], [-1, 28, 28, 1])
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y = tf.keras.layers.Conv2D(16, 8,
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strides=2,
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padding='same',
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activation='relu').apply(input_layer)
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y = tf.keras.layers.MaxPool2D(2, 1).apply(y)
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y = tf.keras.layers.Conv2D(32, 4,
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strides=2,
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padding='valid',
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activation='relu').apply(y)
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y = tf.keras.layers.MaxPool2D(2, 1).apply(y)
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y = tf.keras.layers.Flatten().apply(y)
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y = tf.keras.layers.Dense(32, activation='relu').apply(y)
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logits = tf.keras.layers.Dense(10).apply(y)
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# Define CNN architecture.
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logits = common.get_cnn_model(features)
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# Calculate loss as a vector (to support microbatches in DP-SGD).
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vector_loss = tf.nn.sparse_softmax_cross_entropy_with_logits(
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# Configure the training op (for TRAIN mode).
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if mode == tf.estimator.ModeKeys.TRAIN:
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if FLAGS.dpsgd:
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ledger = privacy_ledger.PrivacyLedger(
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population_size=60000,
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selection_probability=(FLAGS.batch_size / 60000))
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# Use DP version of GradientDescentOptimizer. Other optimizers are
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# available in dp_optimizer. Most optimizers inheriting from
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# tf.train.Optimizer should be wrappable in differentially private
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l2_norm_clip=FLAGS.l2_norm_clip,
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noise_multiplier=FLAGS.noise_multiplier,
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num_microbatches=FLAGS.microbatches,
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ledger=ledger,
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learning_rate=FLAGS.learning_rate)
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training_hooks = [
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EpsilonPrintingTrainingHook(ledger)
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]
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opt_loss = vector_loss
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else:
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optimizer = GradientDescentOptimizer(learning_rate=FLAGS.learning_rate)
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training_hooks = []
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optimizer = tf.train.GradientDescentOptimizer(
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learning_rate=FLAGS.learning_rate)
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opt_loss = scalar_loss
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global_step = tf.train.get_global_step()
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train_op = optimizer.minimize(loss=opt_loss, global_step=global_step)
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# In the following, we pass the mean of the loss (scalar_loss) rather than
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# the vector_loss because tf.estimator requires a scalar loss. This is only
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# used for evaluation and debugging by tf.estimator. The actual loss being
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# minimized is opt_loss defined above and passed to optimizer.minimize().
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return tf.estimator.EstimatorSpec(mode=mode,
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loss=scalar_loss,
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train_op=train_op,
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training_hooks=training_hooks)
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return tf.estimator.EstimatorSpec(
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mode=mode, loss=scalar_loss, train_op=train_op)
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# Add evaluation metrics (for EVAL mode).
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elif mode == tf.estimator.ModeKeys.EVAL:
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labels=labels,
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predictions=tf.argmax(input=logits, axis=1))
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}
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return tf.estimator.EstimatorSpec(mode=mode,
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loss=scalar_loss,
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eval_metric_ops=eval_metric_ops)
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def load_mnist():
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"""Loads MNIST and preprocesses to combine training and validation data."""
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train, test = tf.keras.datasets.mnist.load_data()
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train_data, train_labels = train
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test_data, test_labels = test
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train_data = np.array(train_data, dtype=np.float32) / 255
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test_data = np.array(test_data, dtype=np.float32) / 255
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train_labels = np.array(train_labels, dtype=np.int32)
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test_labels = np.array(test_labels, dtype=np.int32)
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assert train_data.min() == 0.
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assert train_data.max() == 1.
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assert test_data.min() == 0.
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assert test_data.max() == 1.
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assert train_labels.ndim == 1
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assert test_labels.ndim == 1
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return train_data, train_labels, test_data, test_labels
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def main(unused_argv):
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tf.logging.set_verbosity(tf.logging.INFO)
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logging.set_verbosity(logging.INFO)
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if FLAGS.dpsgd and FLAGS.batch_size % FLAGS.microbatches != 0:
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raise ValueError('Number of microbatches should divide evenly batch_size')
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# Load training and test data.
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train_data, train_labels, test_data, test_labels = load_mnist()
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# Instantiate the tf.Estimator.
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mnist_classifier = tf.estimator.Estimator(model_fn=cnn_model_fn,
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model_dir=FLAGS.model_dir)
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# Create tf.Estimator input functions for the training and test data.
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train_input_fn = tf.estimator.inputs.numpy_input_fn(
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x={'x': train_data},
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y=train_labels,
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batch_size=FLAGS.batch_size,
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num_epochs=FLAGS.epochs,
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shuffle=True)
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eval_input_fn = tf.estimator.inputs.numpy_input_fn(
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x={'x': test_data},
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y=test_labels,
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num_epochs=1,
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shuffle=False)
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# Training loop.
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steps_per_epoch = 60000 // FLAGS.batch_size
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for epoch in range(1, FLAGS.epochs + 1):
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start_time = time.time()
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# Train the model for one epoch.
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mnist_classifier.train(input_fn=train_input_fn, steps=steps_per_epoch)
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mnist_classifier.train(
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input_fn=common.make_input_fn('train', FLAGS.batch_size),
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steps=steps_per_epoch)
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end_time = time.time()
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logging.info('Epoch %d time in seconds: %.2f', epoch, end_time - start_time)
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# Evaluate the model and print results
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eval_results = mnist_classifier.evaluate(input_fn=eval_input_fn)
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eval_results = mnist_classifier.evaluate(
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input_fn=common.make_input_fn('test', FLAGS.batch_size, 1))
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test_accuracy = eval_results['accuracy']
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print('Test accuracy after %d epochs is: %.3f' % (epoch, test_accuracy))
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# Compute the privacy budget expended.
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if FLAGS.dpsgd:
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if FLAGS.noise_multiplier > 0.0:
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eps, _ = compute_dp_sgd_privacy_lib.compute_dp_sgd_privacy(
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60000, FLAGS.batch_size, FLAGS.noise_multiplier, epoch, 1e-5)
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print('For delta=1e-5, the current epsilon is: %.2f' % eps)
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else:
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print('Trained with DP-SGD but with zero noise.')
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else:
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print('Trained with vanilla non-private SGD optimizer')
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if __name__ == '__main__':
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app.run(main)
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75
tutorials/mnist_dpsgd_tutorial_common.py
Normal file
75
tutorials/mnist_dpsgd_tutorial_common.py
Normal file
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# Copyright 2020, The TensorFlow Authors.
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#
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# Licensed under the Apache License, Version 2.0 (the "License");
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# you may not use this file except in compliance with the License.
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# You may obtain a copy of the License at
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#
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# http://www.apache.org/licenses/LICENSE-2.0
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#
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# Unless required by applicable law or agreed to in writing, software
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# distributed under the License is distributed on an "AS IS" BASIS,
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# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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# See the License for the specific language governing permissions and
|
||||
# limitations under the License.
|
||||
"""Common tools for DP-SGD MNIST tutorials."""
|
||||
|
||||
# These are not necessary in a Python 3-only module.
|
||||
from __future__ import absolute_import
|
||||
from __future__ import division
|
||||
from __future__ import google_type_annotations
|
||||
from __future__ import print_function
|
||||
|
||||
import tensorflow.compat.v1 as tf
|
||||
import tensorflow_datasets as tfds
|
||||
|
||||
|
||||
def get_cnn_model(features):
|
||||
"""Given input features, returns the logits from a simple CNN model."""
|
||||
input_layer = tf.reshape(features, [-1, 28, 28, 1])
|
||||
y = tf.keras.layers.Conv2D(
|
||||
16, 8, strides=2, padding='same', activation='relu').apply(input_layer)
|
||||
y = tf.keras.layers.MaxPool2D(2, 1).apply(y)
|
||||
y = tf.keras.layers.Conv2D(
|
||||
32, 4, strides=2, padding='valid', activation='relu').apply(y)
|
||||
y = tf.keras.layers.MaxPool2D(2, 1).apply(y)
|
||||
y = tf.keras.layers.Flatten().apply(y)
|
||||
y = tf.keras.layers.Dense(32, activation='relu').apply(y)
|
||||
logits = tf.keras.layers.Dense(10).apply(y)
|
||||
|
||||
return logits
|
||||
|
||||
|
||||
def make_input_fn(split, input_batch_size=256, repetitions=-1, tpu=False):
|
||||
"""Make input function on given MNIST split."""
|
||||
|
||||
def input_fn(params=None):
|
||||
"""A simple input function."""
|
||||
batch_size = params.get('batch_size', input_batch_size)
|
||||
|
||||
def parser(example):
|
||||
image, label = example['image'], example['label']
|
||||
image = tf.cast(image, tf.float32)
|
||||
image /= 255.0
|
||||
label = tf.cast(label, tf.int32)
|
||||
return image, label
|
||||
|
||||
dataset = tfds.load(name='mnist', split=split)
|
||||
dataset = dataset.map(parser).shuffle(60000).repeat(repetitions).batch(
|
||||
batch_size)
|
||||
# If this input function is not meant for TPUs, we can stop here.
|
||||
# Otherwise, we need to explicitly set its shape. Note that for unknown
|
||||
# reasons, returning the latter format causes performance regression
|
||||
# on non-TPUs.
|
||||
if not tpu:
|
||||
return dataset
|
||||
|
||||
# Give inputs statically known shapes; needed for TPUs.
|
||||
images, labels = tf.data.make_one_shot_iterator(dataset).get_next()
|
||||
# return images, labels
|
||||
images.set_shape([batch_size, 28, 28, 1])
|
||||
labels.set_shape([
|
||||
batch_size,
|
||||
])
|
||||
return images, labels
|
||||
|
||||
return input_fn
|
167
tutorials/mnist_dpsgd_tutorial_tpu.py
Normal file
167
tutorials/mnist_dpsgd_tutorial_tpu.py
Normal file
|
@ -0,0 +1,167 @@
|
|||
# Copyright 2020, The TensorFlow Authors.
|
||||
#
|
||||
# Licensed under the Apache License, Version 2.0 (the "License");
|
||||
# you may not use this file except in compliance with the License.
|
||||
# You may obtain a copy of the License at
|
||||
#
|
||||
# http://www.apache.org/licenses/LICENSE-2.0
|
||||
#
|
||||
# Unless required by applicable law or agreed to in writing, software
|
||||
# distributed under the License 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.
|
||||
|
||||
"""Train a CNN on MNIST with DP-SGD optimizer on TPUs."""
|
||||
|
||||
from __future__ import absolute_import
|
||||
from __future__ import division
|
||||
from __future__ import print_function
|
||||
|
||||
import math
|
||||
import time
|
||||
|
||||
from absl import app
|
||||
from absl import flags
|
||||
from absl import logging
|
||||
|
||||
import tensorflow.compat.v1 as tf
|
||||
|
||||
from tensorflow_privacy.privacy.analysis import compute_dp_sgd_privacy_lib
|
||||
from tensorflow_privacy.privacy.optimizers import dp_optimizer
|
||||
from tensorflow_privacy.tutorials import mnist_dpsgd_tutorial_common as common
|
||||
|
||||
flags.DEFINE_boolean(
|
||||
'dpsgd', True, 'If True, train with DP-SGD. If False, '
|
||||
'train with vanilla SGD.')
|
||||
flags.DEFINE_float('learning_rate', .15, 'Learning rate for training')
|
||||
flags.DEFINE_float('noise_multiplier', 0.77,
|
||||
'Ratio of the standard deviation to the clipping norm')
|
||||
flags.DEFINE_float('l2_norm_clip', 1.0, 'Clipping norm')
|
||||
flags.DEFINE_integer('batch_size', 200, 'Batch size')
|
||||
flags.DEFINE_integer('cores', 2, 'Number of TPU cores')
|
||||
flags.DEFINE_integer('epochs', 60, 'Number of epochs')
|
||||
flags.DEFINE_integer(
|
||||
'microbatches', 100, 'Number of microbatches '
|
||||
'(must evenly divide batch_size / cores)')
|
||||
flags.DEFINE_string('model_dir', None, 'Model directory')
|
||||
flags.DEFINE_string('master', None, 'Master')
|
||||
|
||||
FLAGS = flags.FLAGS
|
||||
|
||||
|
||||
def cnn_model_fn(features, labels, mode, params): # pylint: disable=unused-argument
|
||||
"""Model function for a CNN."""
|
||||
|
||||
# Define CNN architecture using tf.keras.layers.
|
||||
logits = common.get_cnn_model(features)
|
||||
|
||||
# Calculate loss as a vector (to support microbatches in DP-SGD).
|
||||
vector_loss = tf.nn.sparse_softmax_cross_entropy_with_logits(
|
||||
labels=labels, logits=logits)
|
||||
# Define mean of loss across minibatch (for reporting through tf.Estimator).
|
||||
scalar_loss = tf.reduce_mean(input_tensor=vector_loss)
|
||||
|
||||
# Configure the training op (for TRAIN mode).
|
||||
if mode == tf.estimator.ModeKeys.TRAIN:
|
||||
if FLAGS.dpsgd:
|
||||
# Use DP version of GradientDescentOptimizer. Other optimizers are
|
||||
# available in dp_optimizer. Most optimizers inheriting from
|
||||
# tf.train.Optimizer should be wrappable in differentially private
|
||||
# counterparts by calling dp_optimizer.optimizer_from_args().
|
||||
optimizer = dp_optimizer.DPGradientDescentGaussianOptimizer(
|
||||
l2_norm_clip=FLAGS.l2_norm_clip,
|
||||
noise_multiplier=FLAGS.noise_multiplier,
|
||||
num_microbatches=FLAGS.microbatches,
|
||||
learning_rate=FLAGS.learning_rate)
|
||||
opt_loss = vector_loss
|
||||
else:
|
||||
optimizer = tf.train.GradientDescentOptimizer(
|
||||
learning_rate=FLAGS.learning_rate)
|
||||
opt_loss = scalar_loss
|
||||
|
||||
# Training with TPUs requires wrapping the optimizer in a
|
||||
# CrossShardOptimizer.
|
||||
optimizer = tf.tpu.CrossShardOptimizer(optimizer)
|
||||
|
||||
global_step = tf.train.get_global_step()
|
||||
train_op = optimizer.minimize(loss=opt_loss, global_step=global_step)
|
||||
|
||||
# In the following, we pass the mean of the loss (scalar_loss) rather than
|
||||
# the vector_loss because tf.estimator requires a scalar loss. This is only
|
||||
# used for evaluation and debugging by tf.estimator. The actual loss being
|
||||
# minimized is opt_loss defined above and passed to optimizer.minimize().
|
||||
return tf.estimator.tpu.TPUEstimatorSpec(
|
||||
mode=mode, loss=scalar_loss, train_op=train_op)
|
||||
|
||||
# Add evaluation metrics (for EVAL mode).
|
||||
elif mode == tf.estimator.ModeKeys.EVAL:
|
||||
|
||||
def metric_fn(labels, logits):
|
||||
predictions = tf.argmax(logits, 1)
|
||||
return {
|
||||
'accuracy':
|
||||
tf.metrics.accuracy(labels=labels, predictions=predictions),
|
||||
}
|
||||
|
||||
return tf.estimator.tpu.TPUEstimatorSpec(
|
||||
mode=mode,
|
||||
loss=scalar_loss,
|
||||
eval_metrics=(metric_fn, {
|
||||
'labels': labels,
|
||||
'logits': logits,
|
||||
}))
|
||||
|
||||
|
||||
def main(unused_argv):
|
||||
logging.set_verbosity(logging.INFO)
|
||||
if FLAGS.dpsgd and FLAGS.batch_size % FLAGS.microbatches != 0:
|
||||
raise ValueError('Number of microbatches should divide evenly batch_size')
|
||||
|
||||
# Instantiate the tf.Estimator.
|
||||
run_config = tf.estimator.tpu.RunConfig(master=FLAGS.master)
|
||||
mnist_classifier = tf.estimator.tpu.TPUEstimator(
|
||||
train_batch_size=FLAGS.batch_size,
|
||||
eval_batch_size=FLAGS.batch_size,
|
||||
model_fn=cnn_model_fn,
|
||||
model_dir=FLAGS.model_dir,
|
||||
config=run_config)
|
||||
|
||||
# Training loop.
|
||||
steps_per_epoch = 60000 // FLAGS.batch_size
|
||||
eval_steps_per_epoch = 10000 // FLAGS.batch_size
|
||||
for epoch in range(1, FLAGS.epochs + 1):
|
||||
start_time = time.time()
|
||||
# Train the model for one epoch.
|
||||
mnist_classifier.train(
|
||||
input_fn=common.make_input_fn(
|
||||
'train', FLAGS.batch_size / FLAGS.cores, tpu=True),
|
||||
steps=steps_per_epoch)
|
||||
end_time = time.time()
|
||||
logging.info('Epoch %d time in seconds: %.2f', epoch, end_time - start_time)
|
||||
|
||||
# Evaluate the model and print results
|
||||
eval_results = mnist_classifier.evaluate(
|
||||
input_fn=common.make_input_fn(
|
||||
'test', FLAGS.batch_size / FLAGS.cores, 1, tpu=True),
|
||||
steps=eval_steps_per_epoch)
|
||||
test_accuracy = eval_results['accuracy']
|
||||
print('Test accuracy after %d epochs is: %.3f' % (epoch, test_accuracy))
|
||||
|
||||
# Compute the privacy budget expended.
|
||||
if FLAGS.dpsgd:
|
||||
if FLAGS.noise_multiplier > 0.0:
|
||||
# Due to the nature of Gaussian noise, the actual noise applied is
|
||||
# equal to FLAGS.noise_multiplier * sqrt(number of cores).
|
||||
eps, _ = compute_dp_sgd_privacy_lib.compute_dp_sgd_privacy(
|
||||
60000, FLAGS.batch_size,
|
||||
FLAGS.noise_multiplier * math.sqrt(FLAGS.cores), epoch, 1e-5)
|
||||
print('For delta=1e-5, the current epsilon is: %.2f' % eps)
|
||||
else:
|
||||
print('Trained with DP-SGD but with zero noise.')
|
||||
else:
|
||||
print('Trained with vanilla non-private SGD optimizer')
|
||||
|
||||
|
||||
if __name__ == '__main__':
|
||||
app.run(main)
|
Loading…
Reference in a new issue