Add ZCDPMonitor and Exponential decay mode.

mindarmour/diff_privacy/monitor/monitor.py

@@ -39,9 +39,8 @@ class PrivacyMonitorFactory:
         Create a privacy monitor class.
 
         Args:
-            policy (str): Monitor policy, 'rdp' is supported by now. RDP
-                means R'enyi differential privacy, which computed based
-                on R'enyi divergence.
+            policy (str): Monitor policy, 'rdp' and 'zcdp' are supported
+                by now.
             args (Union[int, float, numpy.ndarray, list, str]): Parameters
                 used for creating a privacy monitor.
             kwargs (Union[int, float, numpy.ndarray, list, str]): Keyword
@@ -56,7 +55,9 @@ class PrivacyMonitorFactory:
         """
         if policy == 'rdp':
             return RDPMonitor(*args, **kwargs)
-        raise ValueError("Only RDP-policy is supported by now")
+        if policy == 'zcdp':
+            return ZCDPMonitor(*args, **kwargs)
+        raise ValueError("Only RDP-policy or ZCDP-policy is supported by now")
 
 
 class RDPMonitor(Callback):
@@ -97,24 +98,28 @@ class RDPMonitor(Callback):
             of privacy budget would be different for various orders. In order
             to obtain a tighter (smaller) privacy budget estimation, a list
             of orders could be tried. Default: None.
-        noise_decay_mode (str): Decay mode of adding noise while training,
-            which can be 'no_decay', 'Time' or 'Step'. Default: 'Time'.
-        noise_decay_rate (Union[float, None]): Decay rate of noise while
-            training. Default: 6e-4.
+        noise_decay_mode (Union[None, str]): Decay mode of adding noise while
+            training, which can be None, 'Time', 'Step' or 'Exp'. Default: 'Time'.
+        noise_decay_rate (float): Decay rate of noise while training. Default: 6e-4.
         per_print_times　(int): The interval steps of computing and printing
             the privacy budget. Default: 50.
         dataset_sink_mode (bool): If True, all training data would be passed
-            to device(Ascend) at once. If False, training data would be passed
+            to device(Ascend) one-time. If False, training data would be passed
             to device after each step training. Default: False.
 
     Examples:
-        >>> rdp = PrivacyMonitorFactory.create(policy='rdp',
-        >>> num_samples=60000, batch_size=256)
         >>> network = Net()
-        >>> epochs = 2
         >>> net_loss = nn.SoftmaxCrossEntropyWithLogits()
+        >>> epochs = 2
+        >>> norm_clip = 1.0
+        >>> initial_noise_multiplier = 0.01
+        >>> mech = MechanismsFactory().create('Gaussian',
+        >>> norm_bound=norm_clip, initial_noise_multiplier=initial_noise_multiplier)
         >>> net_opt = nn.Momentum(network.trainable_params(), 0.01, 0.9)
-        >>> model = Model(network, net_loss, net_opt)
+        >>> model = DPModel(micro_batches=2, norm_clip=norm_clip,
+        >>> mech=mech, network=network, loss_fn=loss, optimizer=net_opt, metrics=None)
+        >>> rdp = PrivacyMonitorFactory.create(policy='rdp',
+        >>> num_samples=60000, batch_size=256)
         >>> model.train(epochs, ds, callbacks=[rdp], dataset_sink_mode=False)
     """
 
@@ -150,17 +155,16 @@ class RDPMonitor(Callback):
                     msg = 'orders must be greater than 1'
                     LOGGER.error(TAG, msg)
                     raise ValueError(msg)
-        if noise_decay_mode not in ('no_decay', 'Step', 'Time'):
-            msg = "Noise decay mode must be in ('no_decay', 'Step', 'Time')"
+        if noise_decay_mode is not None:
+            if noise_decay_mode not in ('Step', 'Time', 'Exp'):
+                msg = "Noise decay mode must be in ('Step', 'Time', 'Exp')"
                 LOGGER.error(TAG, msg)
                 raise ValueError(msg)
-        if noise_decay_rate is not None:
             noise_decay_rate = check_param_type('noise_decay_rate', noise_decay_rate, float)
             check_param_in_range('noise_decay_rate', noise_decay_rate, 0.0, 1.0)
         check_int_positive('per_print_times', per_print_times)
         check_param_type('dataset_sink_mode', dataset_sink_mode, bool)
 
-        self._total_echo_privacy = None
         self._num_samples = num_samples
         self._batch_size = batch_size
         self._initial_noise_multiplier = initial_noise_multiplier
@@ -232,8 +236,7 @@ class RDPMonitor(Callback):
         if cb_params.cur_step_num % self._per_print_times == 0:
             steps = np.arange(cur_step - self._per_print_times, cur_step + 1)
             eps, delta = self._compute_privacy_steps(list(steps))
-            if np.isnan(eps) or np.isinf(eps) or np.isnan(delta) or np.isinf(
-                    delta):
+            if np.isnan(eps) or np.isinf(eps):
                 msg = 'epoch: {} step: {}, invalid eps, terminating ' \
                       'training.'.format(
                           cb_params.cur_epoch_num, cur_step_in_epoch)
@@ -265,15 +268,10 @@ class RDPMonitor(Callback):
         sampling_rate = self._batch_size / self._num_samples
         noise_stddev_step = self._initial_noise_multiplier
 
-        if self._noise_decay_mode == 'no_decay':
+        if self._noise_decay_mode is None:
             self._rdp += self._compute_rdp(sampling_rate, noise_stddev_step)*len(
                 steps)
         else:
-            if self._noise_decay_rate is None:
-                msg = 'noise_decay_rate in decay-mode cannot be None'
-                LOGGER.error(TAG, msg)
-                raise ValueError(msg)
-
             if self._noise_decay_mode == 'Time':
                 noise_stddev_step = [self._initial_noise_multiplier / (
                     1 + self._noise_decay_rate*step) for step in steps]
@@ -281,6 +279,9 @@ class RDPMonitor(Callback):
             elif self._noise_decay_mode == 'Step':
                 noise_stddev_step = [self._initial_noise_multiplier*(
                     1 - self._noise_decay_rate)**step for step in steps]
+            elif self._noise_decay_mode == 'Exp':
+                noise_stddev_step = [self._initial_noise_multiplier*np.exp(
+                    -step*self._noise_decay_rate) for step in steps]
             self._rdp += sum(
                 [self._compute_rdp(sampling_rate, noise) for noise in
                  noise_stddev_step])
@@ -352,6 +353,203 @@ class RDPMonitor(Callback):
         return np.min(eps)
 
 
+class ZCDPMonitor(Callback):
+    r"""
+    Compute the privacy budget of DP training based on zero-concentrated
+    differential privacy theory (zcdp). According to the reference below,
+    if a randomized mechanism is said to have ρ-ｚCDP, it also satisfies
+    conventional differential privacy (ε, δ) as below:
+
+    .. math::
+        (ρ+２\sqrt{ρlog(1/δ)}, δ)
+
+    Reference: `Concentrated Differentially Private Gradient Descent with
+    Adaptive per-Iteration Privacy Budget <https://arxiv.org/abs/1808.09501>`_
+
+    Args:
+        num_samples (int): The total number of samples in training data sets.
+        batch_size (int): The number of samples in a batch while training.
+        initial_noise_multiplier (Union[float, int]): Ratio of the standard
+            deviation of Gaussian noise divided by the norm_bound, which will
+            be used to calculate privacy spent. Default: 1.5.
+        max_eps (Union[float, int]): The maximum acceptable epsilon budget for
+            DP training, which is used for estimating the max training epochs.
+            Default: 10.0.
+        target_delta (Union[float, int]): Target delta budget for DP training.
+            If target_delta is set to be δ, then the privacy budget δ would be
+            fixed during the whole training process. Default: 1e-3.
+        noise_decay_mode (Union[None, str]): Decay mode of adding noise while
+            training, which can be None, 'Time', 'Step' or 'Exp'. Default: 'Time'.
+        noise_decay_rate (float): Decay rate of noise while training. Default: 6e-4.
+        per_print_times　(int): The interval steps of computing and printing
+            the privacy budget. Default: 50.
+        dataset_sink_mode (bool): If True, all training data would be passed
+            to device(Ascend) one-time. If False, training data would be passed
+            to device after each step training. Default: False.
+
+    Examples:
+        >>> network = Net()
+        >>> net_loss = nn.SoftmaxCrossEntropyWithLogits()
+        >>> epochs = 2
+        >>> norm_clip = 1.0
+        >>> initial_noise_multiplier = 0.01
+        >>> mech = MechanismsFactory().create('Gaussian',
+        >>> norm_bound=norm_clip, initial_noise_multiplier=initial_noise_multiplier)
+        >>> net_opt = nn.Momentum(network.trainable_params(), 0.01, 0.9)
+        >>> model = DPModel(micro_batches=2, norm_clip=norm_clip,
+        >>> mech=mech, network=network, loss_fn=loss, optimizer=net_opt, metrics=None)
+        >>> rdp = PrivacyMonitorFactory.create(policy='rdp',
+        >>> num_samples=60000, batch_size=256)
+        >>> model.train(epochs, ds, callbacks=[rdp], dataset_sink_mode=False)
+    """
+
+    def __init__(self, num_samples, batch_size, initial_noise_multiplier=1.5,
+                 max_eps=10.0, target_delta=1e-3, noise_decay_mode='Time',
+                 noise_decay_rate=6e-4, per_print_times=50, dataset_sink_mode=False):
+        super(ZCDPMonitor, self).__init__()
+        check_int_positive('num_samples', num_samples)
+        check_int_positive('batch_size', batch_size)
+        if batch_size >= num_samples:
+            msg = 'Batch_size must be less than num_samples.'
+            LOGGER.error(TAG, msg)
+            raise ValueError(msg)
+        check_value_positive('initial_noise_multiplier',
+                             initial_noise_multiplier)
+        if noise_decay_mode is not None:
+            if noise_decay_mode not in ('Step', 'Time', 'Exp'):
+                msg = "Noise decay mode must be in ('Step', 'Time', 'Exp')"
+                LOGGER.error(TAG, msg)
+                raise ValueError(msg)
+            noise_decay_rate = check_param_type('noise_decay_rate', noise_decay_rate, float)
+            check_param_in_range('noise_decay_rate', noise_decay_rate, 0.0, 1.0)
+        check_int_positive('per_print_times', per_print_times)
+        check_param_type('dataset_sink_mode', dataset_sink_mode, bool)
+
+        self._num_samples = num_samples
+        self._batch_size = batch_size
+        self._initial_noise_multiplier = initial_noise_multiplier
+        self._max_eps = check_value_positive('max_eps', max_eps)
+        self._target_delta = check_param_in_range('target_delta', target_delta, 0.0, 1.0)
+        self._noise_decay_mode = noise_decay_mode
+        self._noise_decay_rate = noise_decay_rate
+        # initialize zcdp
+        self._zcdp = 0
+        self._per_print_times = per_print_times
+        if dataset_sink_mode:
+            self._per_print_times = int(self._num_samples / self._batch_size)
+
+    def max_epoch_suggest(self):
+        """
+        Estimate the maximum training epochs to satisfy the predefined
+        privacy budget.
+
+        Returns:
+            int, the recommended maximum training epochs.
+
+        Examples:
+            >>> zcdp = PrivacyMonitorFactory.create(policy='zcdp',
+            >>> num_samples=60000, batch_size=32)
+            >>> suggest_epoch = zcdp.max_epoch_suggest()
+        """
+        epoch = 1
+        while epoch < 10000:
+            steps = self._num_samples // self._batch_size
+            eps, _ = self._compute_privacy_steps(
+                list(np.arange((epoch - 1)*steps, epoch*steps + 1)))
+            if eps <= self._max_eps:
+                epoch += 1
+            else:
+                break
+
+        # initialize the zcdp for model training
+        self._zcdp = 0
+        return epoch
+
+    def step_end(self, run_context):
+        """
+        Compute privacy budget after each training step.
+
+        Args:
+            run_context (RunContext): Include some information of the model.
+        """
+        cb_params = run_context.original_args()
+        cur_step = cb_params.cur_step_num
+        cur_step_in_epoch = (cb_params.cur_step_num - 1) % \
+                            cb_params.batch_num + 1
+
+        if cb_params.cur_step_num % self._per_print_times == 0:
+            steps = np.arange(cur_step - self._per_print_times, cur_step + 1)
+            eps, delta = self._compute_privacy_steps(list(steps))
+            if np.isnan(eps) or np.isinf(eps) or np.isnan(delta) or np.isinf(
+                    delta):
+                msg = 'epoch: {} step: {}, invalid eps, terminating ' \
+                      'training.'.format(
+                          cb_params.cur_epoch_num, cur_step_in_epoch)
+                LOGGER.error(TAG, msg)
+                raise ValueError(msg)
+            print("epoch: %s step: %s, delta is %s, eps is %s" % (
+                cb_params.cur_epoch_num, cur_step_in_epoch, delta, eps))
+
+    def _compute_privacy_steps(self, steps):
+        """
+        Compute privacy budget corresponding to steps.
+
+        Args:
+            steps (list): Training steps.
+
+        Returns:
+            float, privacy budget.
+        """
+        noise_stddev_step = self._initial_noise_multiplier
+
+        if self._noise_decay_mode is None:
+            self._zcdp += self._compute_zcdp(noise_stddev_step)*len(
+                steps)
+        else:
+            if self._noise_decay_mode == 'Time':
+                noise_stddev_step = [self._initial_noise_multiplier / (
+                    1 + self._noise_decay_rate*step) for step in steps]
+
+            elif self._noise_decay_mode == 'Step':
+                noise_stddev_step = [self._initial_noise_multiplier*(
+                    1 - self._noise_decay_rate)**step for step in steps]
+            elif self._noise_decay_mode == 'Exp':
+                noise_stddev_step = [self._initial_noise_multiplier*np.exp(
+                    -step*self._noise_decay_rate) for step in steps]
+            self._zcdp += sum(
+                [self._compute_zcdp(noise) for noise in noise_stddev_step])
+        eps = self._compute_eps(self._zcdp)
+
+        return eps, self._target_delta
+
+    def _compute_zcdp(self, noise_stddev):
+        """
+        Compute zcdp according to added noise.
+
+        Args:
+            noise_stddev (float): Noise multiplier.
+
+        Returns:
+            float or numpy.ndarray, zcdp values.
+        """
+        zcdp = 1 / (2*noise_stddev**2)
+        return zcdp
+
+    def _compute_eps(self, zcdp):
+        """
+        Compute eps for given zcdp and delta.
+
+        Args:
+            zcdp (Union[float, numpy.ndarray]): zero-concentrated
+            differential privacy.
+
+        Returns:
+            float, eps budget.
+        """
+        eps = zcdp + 2*np.sqrt(zcdp*np.log(1 / self._target_delta))
+        return eps
+
+
 def _compute_rdp_with_order(sample_rate, noise_stddev, order):
     """
     Compute rdp for each order.

tests/ut/python/diff_privacy/test_monitor.py

@@ -53,7 +53,7 @@ def test_dp_monitor():
     rdp = PrivacyMonitorFactory.create(policy='rdp', num_samples=60000,
                                        batch_size=batch_size,
                                        initial_noise_multiplier=0.4,
-                                       noise_decay_rate=6e-5)
+                                       noise_decay_rate=6e-3)
     suggest_epoch = rdp.max_epoch_suggest()
     LOGGER.info(TAG, 'The recommended maximum training epochs is: %s',
                 suggest_epoch)
@@ -83,7 +83,7 @@ def test_dp_monitor_gpu():
     rdp = PrivacyMonitorFactory.create(policy='rdp', num_samples=60000,
                                        batch_size=batch_size,
                                        initial_noise_multiplier=0.4,
-                                       noise_decay_rate=6e-5)
+                                       noise_decay_rate=6e-3)
     suggest_epoch = rdp.max_epoch_suggest()
     LOGGER.info(TAG, 'The recommended maximum training epochs is: %s',
                 suggest_epoch)
@@ -113,7 +113,7 @@ def test_dp_monitor_cpu():
     rdp = PrivacyMonitorFactory.create(policy='rdp', num_samples=60000,
                                        batch_size=batch_size,
                                        initial_noise_multiplier=0.4,
-                                       noise_decay_rate=6e-5)
+                                       noise_decay_rate=6e-3)
     suggest_epoch = rdp.max_epoch_suggest()
     LOGGER.info(TAG, 'The recommended maximum training epochs is: %s',
                 suggest_epoch)
@@ -129,3 +129,94 @@ def test_dp_monitor_cpu():
                               ["data", "label"])
     ds1.set_dataset_size(batch_size * batches)
     model.train(epochs, ds1, callbacks=[rdp], dataset_sink_mode=False)
+
+
+@pytest.mark.level0
+@pytest.mark.platform_arm_ascend_training
+@pytest.mark.platform_x86_ascend_training
+@pytest.mark.env_card
+@pytest.mark.component_mindarmour
+def test_dp_monitor_zcdp():
+    context.set_context(mode=context.GRAPH_MODE, device_target="Ascend")
+    batch_size = 16
+    batches = 128
+    epochs = 1
+    zcdp = PrivacyMonitorFactory.create(policy='zcdp', num_samples=60000,
+                                        batch_size=batch_size,
+                                        initial_noise_multiplier=0.4,
+                                        noise_decay_rate=6e-3)
+    suggest_epoch = zcdp.max_epoch_suggest()
+    LOGGER.info(TAG, 'The recommended maximum training epochs is: %s',
+                suggest_epoch)
+    network = LeNet5()
+    net_loss = nn.SoftmaxCrossEntropyWithLogits(is_grad=False, sparse=True,
+                                                reduction="mean")
+    net_opt = nn.Momentum(network.trainable_params(), 0.01, 0.9)
+
+    model = Model(network, net_loss, net_opt)
+
+    LOGGER.info(TAG, "============== Starting Training ==============")
+    ds1 = ds.GeneratorDataset(dataset_generator(batch_size, batches),
+                              ["data", "label"])
+    ds1.set_dataset_size(batch_size * batches)
+    model.train(epochs, ds1, callbacks=[zcdp], dataset_sink_mode=False)
+
+
+@pytest.mark.level0
+@pytest.mark.platform_x86_gpu_inference
+@pytest.mark.env_card
+@pytest.mark.component_mindarmour
+def test_dp_monitor_zcdp_gpu():
+    context.set_context(mode=context.GRAPH_MODE, device_target="GPU")
+    batch_size = 16
+    batches = 128
+    epochs = 1
+    zcdp = PrivacyMonitorFactory.create(policy='zcdp', num_samples=60000,
+                                        batch_size=batch_size,
+                                        initial_noise_multiplier=0.4,
+                                        noise_decay_rate=6e-3)
+    suggest_epoch = zcdp.max_epoch_suggest()
+    LOGGER.info(TAG, 'The recommended maximum training epochs is: %s',
+                suggest_epoch)
+    network = LeNet5()
+    net_loss = nn.SoftmaxCrossEntropyWithLogits(is_grad=False, sparse=True,
+                                                reduction="mean")
+    net_opt = nn.Momentum(network.trainable_params(), 0.01, 0.9)
+
+    model = Model(network, net_loss, net_opt)
+
+    LOGGER.info(TAG, "============== Starting Training ==============")
+    ds1 = ds.GeneratorDataset(dataset_generator(batch_size, batches),
+                              ["data", "label"])
+    ds1.set_dataset_size(batch_size * batches)
+    model.train(epochs, ds1, callbacks=[zcdp], dataset_sink_mode=False)
+
+
+@pytest.mark.level0
+@pytest.mark.platform_x86_cpu
+@pytest.mark.env_card
+@pytest.mark.component_mindarmour
+def test_dp_monitor_zcdp_cpu():
+    context.set_context(mode=context.GRAPH_MODE, device_target="CPU")
+    batch_size = 16
+    batches = 128
+    epochs = 1
+    zcdp = PrivacyMonitorFactory.create(policy='zcdp', num_samples=60000,
+                                        batch_size=batch_size,
+                                        initial_noise_multiplier=0.4,
+                                        noise_decay_rate=6e-3)
+    suggest_epoch = zcdp.max_epoch_suggest()
+    LOGGER.info(TAG, 'The recommended maximum training epochs is: %s',
+                suggest_epoch)
+    network = LeNet5()
+    net_loss = nn.SoftmaxCrossEntropyWithLogits(is_grad=False, sparse=True,
+                                                reduction="mean")
+    net_opt = nn.Momentum(network.trainable_params(), 0.01, 0.9)
+
+    model = Model(network, net_loss, net_opt)
+
+    LOGGER.info(TAG, "============== Starting Training ==============")
+    ds1 = ds.GeneratorDataset(dataset_generator(batch_size, batches),
+                              ["data", "label"])
+    ds1.set_dataset_size(batch_size * batches)
+    model.train(epochs, ds1, callbacks=[zcdp], dataset_sink_mode=False)