Moving DTensor to be in the public namespace, to formally add the
documentation page that includes all the public APIs. This includes:
* many path renames and path import fixes
* a dedicated doc page without too much content yet (adding in the next
PRs)
* To preserve the BC for users still using the `torch.distributed._tensor`,
I added a shim script to redirect old path calls to the new module
The BC preserving is evidented by the fact that all DTensor tests are still
working without changing the public imports. So it's safe to land the
changes
Pull Request resolved: https://github.com/pytorch/pytorch/pull/133113
Approved by: https://github.com/XilunWu
ghstack dependencies: #133305, #133306
All the changes brought by the original PR have been addressed in alternative ways in the stack. Why the original PR has to be reverted requires more effort because there is some bad interaction with export.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/131058
Approved by: https://github.com/williamwen42
Reduces the guard overhead from 2.1k units to 1k units. Compared to no-inlining (0.4k units), this reduces the slowdown from 5x to 2.5x.
This introduces unsoundness, but only for hooks for inbuilt nn modules (user defined nn module hooks are fine).
Each builtin nn module adds 4 empty ordered dict checks in the check_fn. This blows up for models with large numbers of builtin nn modules. With this PR, we skip those guards. There is no other easy way I can think of right now to control the guard overhead.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/130420
Approved by: https://github.com/jansel
ghstack dependencies: #130654
----
- We now record on CacheEntry what the compile id that populated it was, so now we can say why a specific frame was rejected
- Add structured log for recompiles under name artifact "recompile_reasons". As it stands, it's not terribly structured, but this was the easiest thing I could do to start
- Slightly reformat multi-reason printing; since we only report one guard failure seems better to have it as a single line
Example output:
```
V0703 10:34:13.273000 140345997743104 torch/_dynamo/guards.py:2590] [0/1] [__recompiles] Recompiling function f in /data/users/ezyang/a/pytorch/b.py:3
V0703 10:34:13.273000 140345997743104 torch/_dynamo/guards.py:2590] [0/1] [__recompiles] triggered by the following guard failure(s):
V0703 10:34:13.273000 140345997743104 torch/_dynamo/guards.py:2590] [0/1] [__recompiles] - 0/0: tensor 'L['x']' size mismatch at index 0. expected 4, actual 5
```
Signed-off-by: Edward Z. Yang <ezyang@meta.com>
Pull Request resolved: https://github.com/pytorch/pytorch/pull/130043
Approved by: https://github.com/anijain2305
Fixes#129601
Background: it's possible that a traceable wrapper subclass will have an optional inner tensor constituent (e.g. NJT's cached min / max sequence lengths). To specify this, the subclass's `__tensor_flatten__()` impl should leave out any unspecified optional inner tensors in the returned list of `attrs`.
This PR guards on the list of inner tensor `attrs` returned in `subclass.__tensor_flatten__()[0]`.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/129618
Approved by: https://github.com/anijain2305
This code is unused because we just inline the `.parameters` call. The code was also wrong because side-effects only track the first level of mutations. An object might not marked mutated if one of the child objects (like a dict) is mutated.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/129316
Approved by: https://github.com/jansel
Improve Dynamo to support the FSDP2 `use_training_state()` context manager.
Test command:
`
pytest -rA test/distributed/_composable/fsdp/test_fully_shard_compile.py::TestFullyShardCompile::test_dynamo_trace_use_training_state
`
Pull Request resolved: https://github.com/pytorch/pytorch/pull/127854
Approved by: https://github.com/yanboliang
Fixes https://github.com/pytorch/pytorch/issues/125720
I was earlier worried that DELETE_* or STORE_* on referent values should result in a graph break, because they could invalidate the weak ref. But then @zou3519 pointed out that weakref invalidation will happen EVENTUALLY, CPython provides no guarantees when the weakref will be invalidated (even when the user calls del x and x is the last reference).
So any code that relies on del x to invalidate the weakref of x right away is BAD code. CPython provide no guarantees. Therefore we can (ab)use this nuance, and can just ignore DELETE_* or STORE_* on the referent objects.
The only corner case is when Dynamo is reconstructing the weakref object. Dynamo will have a hard time being correct here, so just SKIP_FRAME on such a case. This is rare.
Cpython notes
1) https://docs.python.org/3/library/weakref.html
2) https://docs.python.org/3/reference/datamodel.html#index-2
Pull Request resolved: https://github.com/pytorch/pytorch/pull/128533
Approved by: https://github.com/jansel
Reduces compile time of MobileBertForMaskedLM model from 39 seconds to 26 seconds. This was a regression introduced by #125202. Before that PR, compile time was 24 seconds. The extra two seconds is just because we are going through enormous number of guards.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/127377
Approved by: https://github.com/jansel
The big idea is that floats are treated as Tensors on input/output to the FX graph, but on the inside, we immediately call item() on the synthetic Tensor and record regular float operations on it. Canonicalization to Tensor operations will happen in a standalone FX pass. This behavior is controlled by `specialize_float` config variable when set to False.
The generated graph looks like this for the test `test_unspec_float_output`:
```
def forward(self, L_x_: "f32[3]", L_y_: "f32[]"):
l_x_ = L_x_
l_y_ = L_y_
# File: /data/users/ezyang/a/pytorch/test/dynamo/test_unspec.py:511 in f, code: return x + 1, y * 2
add: "f32[3]" = l_x_ + 1; l_x_ = None
item: "Sym(zf0)" = l_y_.item(); l_y_ = None
mul: "Sym(2*zf0)" = item * 2; item = None
scalar_tensor: "f32[]" = torch.scalar_tensor(mul); mul = None
return (add, scalar_tensor)
```
The ingredients:
* **torch/_dynamo/variables/builder.py** When `specialize_float` is False, we wrap float literals with `wrap_symfloat`. This is an unholy mashup of `wrap_symint` and `wrap_unspecialized_primitive`. The overall strategy is that we first generate a tensor argument (because that's what we want to show up into the FX graph), but then immediately call item() on the tensor argument to get a SymNodeVariable, which we will do the rest of the tracing with. Importantly, this SymNodeVariable is backed with the source of the original float: this means we can guard on the resulting value (something we could NOT do with UnspecializedPythonVariable). This has to be done manually, because if you literally call item() on the tensor, you will end up with an unbacked float. There is a bit of copy paste from wrap_symint and wrap_unspecialized_primitive which we can try to factor out, but this really is its own thing and you should review every line of code in the function.
* **torch/fx/experimental/symbolic_shapes.py** We now can generate guards on float inputs, and these guards are handled inside of ShapeEnv. So we need to be able to allocate (backed!) float symbols, and produce guards for them. Fairly straightforward generalization.
* **torch/_dynamo/codegen.py** I also need to maintain the invariant that there are no float outputs to the FX graph. I chose to do this at codegen time. When we detect a SymNodeVariable on the return stack for a float, we on the fly convert it (via `as_tensor`) to a TensorVariable, which is the true output. We then special case the output bytecode to call item() on it again. The tensor conversion is memoized on SymNodeVariable since we typically run the code generation process twice.
Signed-off-by: Edward Z. Yang <ezyang@meta.com>
Pull Request resolved: https://github.com/pytorch/pytorch/pull/125325
Approved by: https://github.com/lezcano, https://github.com/jansel
We guard on key order
1) When a key is a non-constant object
2) When we actually need key order - like .values, .items etc
For dicts/OrderedDicts that do not require key order guarding, we just rely on usual `GuardManger + DictGetItemGuardAccessor`. This is faster than going through the `list(d.keys())` based design for OrderedDicts.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/124779
Approved by: https://github.com/jansel