[DTensor] Ensured grad_placements was tuple
#113925
Closed
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
[ghstack-poisoned]
This was referenced Nov 17, 2023
🔗 Helpful Links🧪 See artifacts and rendered test results at hud.pytorch.org/pr/113925
Note: Links to docs will display an error until the docs builds have been completed. ✅ No FailuresAs of commit 03e7d12 with merge base 140c54e ( This comment was automatically generated by Dr. CI and updates every 15 minutes. |
This was referenced Nov 17, 2023
[ghstack-poisoned]
This was referenced Nov 20, 2023
awgu
added
ciflow/trunk
pytorchmergebot
pushed a commit
that referenced
this pull request
Nov 21, 2023
This is a replacement for #113922. I think we can still leave the check for negative shard dimension in `compute_local_shape_and_global_offset` and replace the normalization logic with an assert. This should provide us a stack trace to see which user-facing API did not normalize the dim as expected. Pull Request resolved: #114141 Approved by: https://github.com/wanchaol ghstack dependencies: #113919, #113924, #114134, #113925, #113930
pytorchmergebot
pushed a commit
that referenced
this pull request
Nov 21, 2023
**Overview** Generally, I think we can try to freeze as many of these classes used in DTensor sharding propagation as possible so that we can cache hashes. This PR targets hashing `DTensorSpec`, which turns out to be relatively expensive. **Details** It looks like `tensor_meta` is only updated in `_wrap_output_spec_tensor_meta`, which only runs if the propagation was not cached: https://github.com/pytorch/pytorch/blob/ae94c7e491e22f58d3df66571c1a568e51d70acd/torch/distributed/_tensor/sharding_prop.py#L137 https://github.com/pytorch/pytorch/blob/ae94c7e491e22f58d3df66571c1a568e51d70acd/torch/distributed/_tensor/sharding_prop.py#L153 In that case, I think we can cache the hash for the `DTensorSpec` and only update it when one of the hashed attributes changes, which we only really expect to happen for `tensor_meta`. To ensure correctness, we need that all hashed attributes are immutable. - `DeviceMesh` caches its hash: https://github.com/pytorch/pytorch/blob/a9134fa99a8986adf478a12db2ea5729d24554db/torch/distributed/_device_mesh.py#L181 - This PR makes each `Placement` a frozen `dataclass`, making them immutable (relying on the fact that they do not have references to any mutable objects). - `TensorMeta` is a `NamedTuple` of `torch.Size`, `Tuple[int, ...]`, and `torch.dtype`, so it is immutable: https://github.com/pytorch/pytorch/blob/9916d8a9eaaf2c05c131f2a2dbe9eabeeaa9dffc/torch/distributed/_tensor/placement_types.py#L369-L375 **Example** For some simple small GPT model: Before: 0.125 ms <img width="509" alt="Screenshot 2023-11-16 at 10 08 05 PM" src="https://github.com/pytorch/pytorch/assets/31054793/10e59401-f635-431f-80b5-1b48df3a706e"> After: 0.048 ms <img width="294" alt="Screenshot 2023-11-16 at 10 08 47 PM" src="https://github.com/pytorch/pytorch/assets/31054793/09a3b0b9-f68c-4afc-bca1-c29a4b01c2fb"> The overall Adam CPU step time decreases from 7.647 ms to 6.451 ms. Pull Request resolved: #113915 Approved by: https://github.com/wanchaol ghstack dependencies: #113919, #113924, #114134, #113925, #113930, #114141
pytorchmergebot
pushed a commit
that referenced
this pull request
Nov 21, 2023
This is a nit change to save one `isinstance` call for when `dim` is not `None` but the placement is not `Shard`. Pull Request resolved: #114140 Approved by: https://github.com/Skylion007, https://github.com/wanchaol ghstack dependencies: #113919, #113924, #114134, #113925, #113930, #114141, #113915
pytorchmergebot
pushed a commit
that referenced
this pull request
Nov 22, 2023
This is a forward fix for #113781. We lazily compute the hash so that we do not try to compute the hash on `SymInt`s (for the stride) during Dynamo tracing. Tested via: ``` python test/distributed/_tensor/test_dtensor_compile.py -k test_2d_fsdp_tp_ac_compile ``` Pull Request resolved: #114322 Approved by: https://github.com/wanchaol ghstack dependencies: #113919, #113924, #114134, #113925, #113930, #114141, #113915, #114140
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Stack from ghstack (oldest at bottom):
isinstancecall inis_shard#114140DTensorSpec#113915distribute_tensor#113930grad_placementswas tuple #113925from_local#114134redistribute#113924_Partial,Replicatefrozen dataclasses #113919