**Problem & Solution:**
Assume we have something like:
```
x = some_op(...)
x0 = x[0]
do_something_with_and_is_last_use_of(x0)
do_a_bunch_of_other_things()
x1 = x[1]
```
In this case, the memory associated with `x0` cannot be released until `x1 = x[1]`. Since `x1 = x[1]` does not use additional memory, it would be beneficial to move and `x1 = x[1]` and all such `getitem` operations to be immediately after `x = some_op(...)` such as
```
x = some_op(...)
x0 = x[0]
x1 = x[1]
do_something_with_and_is_last_use_of(x0)
do_a_bunch_of_other_things()
```
**Results:**
For instance, for the `res2net101_26w_4s` model in pytorch benchmark, when running with `aot_eager` backend and with `activation_memory_budget=0.4`, the peak memory are
* baseline: 7.73GiB
* with the chage: 6.45GiB
As a sanity check, for the same setting with `inductor` backend, the peak memory is not regressed.
cc and credit to @ShatianWang for noticing this issue.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/155809
Approved by: https://github.com/fmassa, https://github.com/bdhirsh
**Problem & Solution:**
Assume we have something like:
```
x = some_op(...)
x0 = x[0]
do_something_with_and_is_last_use_of(x0)
do_a_bunch_of_other_things()
x1 = x[1]
```
In this case, the memory associated with `x0` cannot be released until `x1 = x[1]`. Since `x1 = x[1]` does not use additional memory, it would be beneficial to move and `x1 = x[1]` and all such `getitem` operations to be immediately after `x = some_op(...)` such as
```
x = some_op(...)
x0 = x[0]
x1 = x[1]
do_something_with_and_is_last_use_of(x0)
do_a_bunch_of_other_things()
```
**Results:**
For instance, for the `res2net101_26w_4s` model in pytorch benchmark, when running with `aot_eager` backend and with `activation_memory_budget=0.4`, the peak memory are
* baseline: 7.73GiB
* with the chage: 6.45GiB
As a sanity check, for the same setting with `inductor` backend, the peak memory is not regressed.
cc and credit to @ShatianWang for noticing this issue.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/155809
Approved by: https://github.com/fmassa, https://github.com/bdhirsh
ghstack dependencies: #155943
aten.empty is almost always fusible into its consumer, so we never CSE
it. This fixes a bug that looks like the following:
```py
@torch.library.custom_op("_reinplacing::sin_cos", mutates_args={"out_sin", "out_cos"})
def sin_cos(x: torch.Tensor, out_sin: torch.Tensor, out_cos: torch.Tensor) -> None:
out_sin.copy_(x.sin())
out_cos.copy_(x.cos())
@torch.compile
def f(x):
out0 = torch.empty_like(x)
out1 = torch.empty_like(x)
sin_cos(x, out0, out1)
return x.clone(), out0, out1
x = torch.randn(3, requires_grad=True)
f(x)
```
- cse would de-duplicate the empty nodes
- reinplacing would add an additional clone (because it can't write to
both tensors at the same time)
- the clone lowers into a new buffer + a copy_ kernel
- the copy_ kernel is unnecessary because "empty" is special - all reinplacing needed was an additional
buffer, it doesn't matter what the values are.
We could attempt to fix this on the reinplacing side but this seemed
better as a partitioner heuristic and the reinplacing fix is a bit more
tricky (we'd need to identify that the op never reads from the empty
node).
Test Plan:
- new test (the old number was 27, the new number is 21, so this PR
helped).
Pull Request resolved: https://github.com/pytorch/pytorch/pull/134703
Approved by: https://github.com/yf225
ghstack dependencies: #134466, #134490, #134491
This is a lot of files changed! Don't panic! Here's how it works:
* Previously, we set `follow_imports = silent` for our mypy.ini configuration. Per https://mypy.readthedocs.io/en/stable/running_mypy.html#follow-imports, what this does is whenever we have an import to a module which is not listed as a file to be typechecked in mypy, we typecheck it as normal but suppress all errors that occurred in that file.
* When mypy is run inside lintrunner, the list of files is precisely the files covered by the glob in lintrunner.toml, but with files in excludes excluded.
* The top-level directive `# mypy: ignore-errors` instructs mypy to typecheck the file as normal, but ignore all errors.
* Therefore, it should be equivalent to set `follow_imports = normal`, if we put `# mypy: ignore-errors` on all files that were previously excluded from the file list.
* Having done this, we can remove the exclude list from .lintrunner.toml, since excluding a file from typechecking is baked into the files themselves.
* torch/_dynamo and torch/_inductor were previously in the exclude list, because they were covered by MYPYINDUCTOR. It is not OK to mark these as `# mypy: ignore-errors` as this will impede typechecking on the alternate configuration. So they are temporarily being checked twice, but I am suppressing the errors in these files as the configurations are not quite the same. I plan to unify the configurations so this is only a temporary state.
* There were some straggler type errors after these changes somehow, so I fixed them as needed. There weren't that many.
In the future, to start type checking a file, just remove the ignore-errors directive from the top of the file.
The codemod was done with this script authored by GPT-4:
```
import glob
exclude_patterns = [
...
]
for pattern in exclude_patterns:
for filepath in glob.glob(pattern, recursive=True):
if filepath.endswith('.py'):
with open(filepath, 'r+') as f:
content = f.read()
f.seek(0, 0)
f.write('# mypy: ignore-errors\n\n' + content)
```
Signed-off-by: Edward Z. Yang <ezyang@meta.com>
Pull Request resolved: https://github.com/pytorch/pytorch/pull/118414
Approved by: https://github.com/thiagocrepaldi, https://github.com/albanD
This will be the last disruptive functorch internals change.
Why are we moving these files?
- As a part of rationalizing functorch we are moving the code in
functorch/_src to torch/_functorch
- This is so that we can offer the functorch APIs as native PyTorch APIs
(coming soon) and resolve some internal build issues.
Why are we moving all of these files at once?
- It's better to break developers all at once rather than many times
Test Plan:
- wait for tests
Pull Request resolved: https://github.com/pytorch/pytorch/pull/90091
Approved by: https://github.com/anijain2305, https://github.com/ezyang
This will be the last disruptive functorch internals change.
Why are we moving these files?
- As a part of rationalizing functorch we are moving the code in
functorch/_src to torch/_functorch
- This is so that we can offer the functorch APIs as native PyTorch APIs
(coming soon) and resolve some internal build issues.
Why are we moving all of these files at once?
- It's better to break developers all at once rather than many times
Test Plan:
- wait for tests
Pull Request resolved: https://github.com/pytorch/pytorch/pull/88756
Approved by: https://github.com/ezyang
