⬆️ Update torch requirement from ~=2.4.0 to >=2.4,<2.6

[dependabot]

Updates the requirements on torch to permit the latest version.

Release notes

Sourced from torch's releases.

PyTorch 2.5.0 Release, SDPA CuDNN backend, Flex Attention

PyTorch 2.5 Release Notes

• Highlights
• Backwards Incompatible Change
• Deprecations
• New Features
• Improvements
• Bug fixes
• Performance
• Documentation
• Developers
• Security

Highlights

We are excited to announce the release of PyTorch® 2.5! This release features a new CuDNN backend for SDPA, enabling speedups by default for users of SDPA on H100s or newer GPUs. As well, regional compilation of torch.compile offers a way to reduce the cold start up time for torch.compile by allowing users to compile a repeated nn.Module (e.g. a transformer layer in LLM) without recompilations. Finally, TorchInductor CPP backend offers solid performance speedup with numerous enhancements like FP16 support, CPP wrapper, AOT-Inductor mode, and max-autotune mode. This release is composed of 4095 commits from 504 contributors since PyTorch 2.4. We want to sincerely thank our dedicated community for your contributions. As always, we encourage you to try these out and report any issues as we improve 2.5. More information about how to get started with the PyTorch 2-series can be found at our Getting Started page. As well, please check out our new ecosystem projects releases with TorchRec and TorchFix.

Beta	Prototype
CuDNN backend for SDPA	FlexAttention
torch.compile regional compilation without recompilations	Compiled Autograd
TorchDynamo added support for exception handling & MutableMapping types	Flight Recorder
TorchInductor CPU backend optimization	Max-autotune Support on CPU with GEMM Template
	TorchInductor on Windows
	FP16 support on CPU path for both eager mode and TorchInductor CPP backend
	Autoload Device Extension
	Enhanced Intel GPU support

*To see a full list of public feature submissions click here.

BETA FEATURES

[Beta] CuDNN backend for SDPA

The cuDNN "Fused Flash Attention" backend was landed for torch.nn.functional.scaled_dot_product_attention. On NVIDIA H100 GPUs this can provide up to 75% speed-up over FlashAttentionV2. This speedup is enabled by default for all users of SDPA on H100 or newer GPUs.

[Beta] torch.compile regional compilation without recompilations

Regional compilation without recompilations, via torch._dynamo.config.inline_inbuilt_nn_modules which default to True in 2.5+. This option allows users to compile a repeated nn.Module (e.g. a transformer layer in LLM) without recompilations. Compared to compiling the full model, this option can result in smaller compilation latencies with 1%-5% performance degradation compared to full model compilation.

See the tutorial for more information.

[Beta] TorchInductor CPU backend optimization

This feature advances Inductor’s CPU backend optimization, including CPP backend code generation and FX fusions with customized CPU kernels. The Inductor CPU backend supports vectorization of common data types and all Inductor IR operations, along with the static and symbolic shapes. It is compatible with both Linux and Windows OS and supports the default Python wrapper, the CPP wrapper, and AOT-Inductor mode.

Additionally, it extends the max-autotune mode of the GEMM template (prototyped in 2.5), offering further performance gains. The backend supports various FX fusions, lowering to customized kernels such as oneDNN for Linear/Conv operations and SDPA. The Inductor CPU backend consistently achieves performance speedups across three benchmark suites—TorchBench, Hugging Face, and timms—outperforming eager mode in 97.5% of the 193 models tested.

PROTOTYPE FEATURES

[Prototype] FlexAttention

We've introduced a flexible API that enables implementing various attention mechanisms such as Sliding Window, Causal Mask, and PrefixLM with just a few lines of idiomatic PyTorch code. This API leverages torch.compile to generate a fused FlashAttention kernel, which eliminates extra memory allocation and achieves performance comparable to handwritten implementations. Additionally, we automatically generate the backwards pass using PyTorch's autograd machinery. Furthermore, our API can take advantage of sparsity in the attention mask, resulting in significant improvements over standard attention implementations.

For more information and examples, please refer to the official blog post and Attention Gym.

... (truncated)

Changelog

Sourced from torch's changelog.

Releasing PyTorch

• Release Compatibility Matrix
• Release Cadence
• General Overview
  • Frequently Asked Questions
• Cutting a release branch preparations
• Cutting release branches
  • pytorch/pytorch
  • pytorch/builder / PyTorch domain libraries
  • Making release branch specific changes for PyTorch
  • Making release branch specific changes for domain libraries
• Running Launch Execution team Core XFN sync
• Drafting RCs (https://github.com/pytorch/pytorch/blob/main/Release Candidates) for PyTorch and domain libraries
  • Release Candidate Storage
  • Release Candidate health validation
  • Cherry Picking Fixes
    • How to do Cherry Picking
  • Cherry Picking Reverts
• Preparing and Creating Final Release candidate
• Promoting RCs to Stable
• Additional Steps to prepare for release day
  • Modify release matrix
  • Open Google Colab issue
• Patch Releases
  • Patch Release Criteria
  • Patch Release Process
    • Patch Release Process Description
    • Triage
    • Issue Tracker for Patch releases
    • Building a release schedule / cherry picking
    • Building Binaries / Promotion to Stable
• Hardware / Software Support in Binary Build Matrix
  • Python
  • Accelerator Software
    • Special support cases
  • Operating Systems
• Submitting Tutorials
• Special Topics
  • Updating submodules for a release
  • Triton dependency for the release

Release Compatibility Matrix

Following is the Release Compatibility Matrix for PyTorch releases:

... (truncated)

Commits

• 32f585d [Release only] use triton 3.1.x from pypi (#137895)
• 417a076 [split build] move periodic split builds into own concurrency group (#135510)...
• 119e734 [RELEASE-ONLY CHANGES] Fix dependency on filesystem on Linux (#137242)
• 783a6a4 [MPS] Add regression test for fft.fftfreq (#137215)
• 5375201 [MPS] Add missing dispatch to rshift.Tensor (#137212)
• 1de132e [MPS] Fix 5D+ reductions over negative dimentions (#137211)
• 0b1b609 [NCCL] Don't override waitUntilInitialized's setting of `comm->initialized_...
• 0b45af9 Fix addmm silent correctness on aarch64 (#137208)
• 1a0b166 [ONNX] Add assertion nodes to ignoring list (#137214)
• 3a541ef Clarify that libtorch API is C++17 compatible (#137206)
• Additional commits viewable in compare view

You can trigger a rebase of this PR by commenting @dependabot rebase.

---

Dependabot commands and options

You can trigger Dependabot actions by commenting on this PR:

• @dependabot rebase will rebase this PR
• @dependabot recreate will recreate this PR, overwriting any edits that have been made to it
• @dependabot merge will merge this PR after your CI passes on it
• @dependabot squash and merge will squash and merge this PR after your CI passes on it
• @dependabot cancel merge will cancel a previously requested merge and block automerging
• @dependabot reopen will reopen this PR if it is closed
• @dependabot close will close this PR and stop Dependabot recreating it. You can achieve the same result by closing it manually
• @dependabot show <dependency name> ignore conditions will show all of the ignore conditions of the specified dependency
• @dependabot ignore this major version will close this PR and stop Dependabot creating any more for this major version (unless you reopen the PR or upgrade to it yourself)
• @dependabot ignore this minor version will close this PR and stop Dependabot creating any more for this minor version (unless you reopen the PR or upgrade to it yourself)
• @dependabot ignore this dependency will close this PR and stop Dependabot creating any more for this dependency (unless you reopen the PR or upgrade to it yourself)

Note
Automatic rebases have been disabled on this pull request as it has been open for over 30 days.