Files
wehub-resource-sync ba4be087d5
Create PR to main with cherry-pick from release / cherry-pick (push) Failing after 0s
CICD NeMo / pre-flight (push) Failing after 0s
CICD NeMo / configure (push) Has been skipped
Build, validate, and release Neural Modules / pre-flight (push) Failing after 1s
CICD NeMo / code-linting (push) Has been skipped
Build, validate, and release Neural Modules / release (push) Has been skipped
Build, validate, and release Neural Modules / release-summary (push) Has been cancelled
CICD NeMo / cicd-test-container-build (push) Has been cancelled
CICD NeMo / cicd-import-tests (push) Has been cancelled
CICD NeMo / L0_Setup_Test_Data_And_Models (push) Has been cancelled
CICD NeMo / cicd-main-unit-tests (push) Has been cancelled
CICD NeMo / cicd-main-speech (push) Has been cancelled
CICD NeMo / Nemo_CICD_Test (push) Has been cancelled
CICD NeMo / Coverage (e2e) (push) Has been cancelled
CICD NeMo / Coverage (unit-test) (push) Has been cancelled
CodeQL / Analyze (python) (push) Has been cancelled
CICD NeMo / cicd-wait-in-queue (push) Has been cancelled
chore: import upstream snapshot with attribution
2026-07-13 13:28:58 +08:00

65 lines
2.4 KiB
Python

# Copyright (c) 2026, NVIDIA CORPORATION. All rights reserved.
#
# 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.
from typing import Any
import torch
from nemo.utils import logging
def patch_flashoptim_uneven_shard_support(optimizer) -> None:
"""Patch flashoptim to handle FSDP2 unevenly-sharded parameters in DCP.
FlashOptim <= 0.1.3 raises ``ValueError`` when saving optimizer state for
parameters whose shard dimension is not evenly divisible by the FSDP mesh
size. The root cause is that ``DTensor.from_local()`` is called without an
explicit ``shape``, so it infers ``global = local * mesh_size`` which is
wrong for padded (uneven) shards.
This patch replaces ``_wrap_state_as_dtensor`` on the optimizer class so
that ``shape=param.shape`` and ``stride=param.stride()`` are always passed,
which is correct for both even and uneven shards.
"""
klass = type(optimizer)
if not hasattr(klass, "_wrap_state_as_dtensor"):
return
if getattr(klass, "_nemo_patched_uneven_shard", False):
return
@staticmethod
def _fixed_wrap_state_as_dtensor(state: dict[str, Any], param: torch.Tensor) -> None: # noqa: UP006
if not hasattr(param, "device_mesh"):
return
from torch.distributed.tensor import DTensor
mesh = param.device_mesh
placements = param.placements
for key, val in state.items():
if isinstance(val, torch.Tensor) and not isinstance(val, DTensor) and val.dim() > 0:
state[key] = DTensor.from_local(
val,
mesh,
placements,
shape=param.shape,
stride=param.stride(),
)
klass._wrap_state_as_dtensor = _fixed_wrap_state_as_dtensor
klass._nemo_patched_uneven_shard = True
logging.info("Patched flashoptim %s to support unevenly-sharded FSDP2 parameters in DCP.", klass.__name__)