rocm_jax/jax/_src/partition_spec.py
Peter Hawkins d4336c1d8c Improve the sharding documentation.
* do some proofreading.
* add PmapSharding and GSPMDSharding, which are both missing.
2023-08-03 11:12:02 -04:00

51 lines
1.6 KiB
Python

# Copyright 2021 The JAX 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
#
# https://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.
class _UnconstrainedPartitionSingleton:
def __str__(self):
return "UNCONSTRAINED"
# Unconstrained sentinel value for PartitionSpec, representing a dimension for
# which the user wants XLA to assign the best partitioning.
# TODO(yashkatariya): May rename to AUTO.
_UNCONSTRAINED_PARTITION = _UnconstrainedPartitionSingleton()
class PartitionSpec(tuple):
"""Tuple describing how to partition an array across a mesh of devices.
Each element is either ``None``, a string, or a tuple of strings.
See the documentation of :class:`jax.sharding.NamedSharding` for more details.
This class exists so JAX's pytree utilities can distinguish a partition
specifications from tuples that should be treated as pytrees.
"""
# A sentinel value representing a dim is unconstrained.
UNCONSTRAINED = _UNCONSTRAINED_PARTITION
def __init__(self, *partitions):
pass
def __new__(cls, *partitions):
return tuple.__new__(PartitionSpec, partitions)
def __repr__(self):
return "PartitionSpec%s" % tuple.__repr__(self)
def __reduce__(self):
return (PartitionSpec, tuple(self))