tf.distribute.CrossDeviceOps

Base class for cross-device reduction and broadcasting algorithms.

View aliases

Compat aliases for migration

tf.compat.v1.distribute.CrossDeviceOps

tf.distribute.CrossDeviceOps()

The main purpose of this class is to be passed to tf.distribute.MirroredStrategy in order to choose among different cross device communication implementations. Prefer using the methods of tf.distribute.Strategy instead of the ones of this class.

Implementations:

Methods

`batch_reduce`

View source

batch_reduce(
    reduce_op, value_destination_pairs, options=None
)

Reduce values to destinations in batches.

See tf.distribute.StrategyExtended.batch_reduce_to. This can only be called in the cross-replica context.

Args
`reduce_op`	a `tf.distribute.ReduceOp` specifying how values should be combined.
`value_destination_pairs`	a sequence of (value, destinations) pairs. See `tf.distribute.CrossDeviceOps.reduce` for descriptions.
`options`	a `tf.distribute.experimental.CommunicationOptions`. See `tf.distribute.experimental.CommunicationOptions` for details.

Returns
A list of `tf.Tensor` or `tf.distribute.DistributedValues`, one per pair in `value_destination_pairs`.

Raises
`ValueError`	if `value_destination_pairs` is not an iterable of tuples of `tf.distribute.DistributedValues` and destinations.

`batch_reduce_implementation`

View source

batch_reduce_implementation(
    reduce_op, value_destination_pairs, options
)

Implementation of batch_reduce.

Overriding this method is useful for subclass implementers.

Args
`reduce_op`	a `tf.distribute.ReduceOp` specifying how values should be combined.
`value_destination_pairs`	a sequence of (value, destinations) pairs. See `reduce` for descriptions.
`options`	a `tf.distribute.experimental.CommunicationOptions`. See `tf.distribute.experimental.CommunicationOptions` for details.

Returns
A list of `tf.Tensor` or `tf.distribute.DistributedValues`, one per pair in `value_destination_pairs`.

Raises
`ValueError`	if `value_destination_pairs` is not an iterable of tuples of `tf.distribute.DistributedValues` and destinations.

`broadcast`

View source

broadcast(
    tensor, destinations
)

Broadcast tensor to destinations.

This can only be called in the cross-replica context.

Args
`tensor`	a `tf.Tensor` like object. The value to broadcast.
`destinations`	a `tf.distribute.DistributedValues`, a `tf.Variable`, a `tf.Tensor` alike object, or a device string. It specifies the devices to broadcast to. Note that if it's a `tf.Variable`, the value is broadcasted to the devices of that variable, this method doesn't update the variable.

Returns
A `tf.Tensor` or `tf.distribute.DistributedValues`.

`broadcast_implementation`

View source

broadcast_implementation(
    tensor, destinations
)

Implementation of broadcast.

Args
`tensor`	a `tf.Tensor` like object. The value to broadcast.
`destinations`	a `tf.distribute.DistributedValues`, a `tf.Variable`, a `tf.Tensor` alike object, or a device string. It specifies the devices to broadcast to. `destinations`. Note that if it's a `tf.Variable`, the value is broadcasted to the devices of that variable, this method doesn't update the variable.

Returns
A `tf.Tensor` or `tf.distribute.DistributedValues`.

`reduce`

View source

reduce(
    reduce_op, per_replica_value, destinations, options=None
)

Reduce per_replica_value to destinations.

See tf.distribute.StrategyExtended.reduce_to. This can only be called in the cross-replica context.

Args
`reduce_op`	a `tf.distribute.ReduceOp` specifying how values should be combined.
`per_replica_value`	a `tf.distribute.DistributedValues`, or a `tf.Tensor` like object.
`destinations`	a `tf.distribute.DistributedValues`, a `tf.Variable`, a `tf.Tensor` alike object, or a device string. It specifies the devices to reduce to. To perform an all-reduce, pass the same to `value` and `destinations`. Note that if it's a `tf.Variable`, the value is reduced to the devices of that variable, and this method doesn't update the variable.
`options`	a `tf.distribute.experimental.CommunicationOptions`. See `tf.distribute.experimental.CommunicationOptions` for details.

Returns
A `tf.Tensor` or `tf.distribute.DistributedValues`.

Raises
`ValueError`	if per_replica_value can't be converted to a `tf.distribute.DistributedValues` or if destinations is not a string, `tf.Variable` or `tf.distribute.DistributedValues`.

`reduce_implementation`

View source

reduce_implementation(
    reduce_op, per_replica_value, destinations, options
)

Implementation of reduce.

Overriding this method is useful for subclass implementers.

Args
`reduce_op`	a `tf.distribute.ReduceOp` specifying how values should be combined.
`per_replica_value`	a `tf.distribute.DistributedValues`, or a `tf.Tensor` like object.
`destinations`	a `tf.distribute.DistributedValues`, a `tf.Variable`, a `tf.Tensor` alike object, or a device string. It specifies the devices to reduce to. To perform an all-reduce, pass the same to `value` and `destinations`. Note that if it's a `tf.Variable`, the value is reduced to the devices of that variable, this method doesn't update the variable.
`options`	a `tf.distribute.experimental.CommunicationOptions`. See `tf.distribute.experimental.CommunicationOptions` for details.

Returns
A `tf.Tensor` or `tf.distribute.DistributedValues`.

Raises
`ValueError`	if per_replica_value can't be converted to a `tf.distribute.DistributedValues` or if destinations is not a string, `tf.Variable` or `tf.distribute.DistributedValues`.