microsoft/onnxruntime v1.29.1

ONNX Runtime v1.29.1

Repository: microsoft/onnxruntime

Tag: v1.29.1

Published: 2026-09-10T05:26:07Z

Prerelease: no

Release notes: This is a patch release on top of v1.29.0, containing GroupQueryAttention capability and KV-cache layout improvements, plugin Execution Provider performance tooling updates, and targeted graph and optimizer fixes.

GroupQueryAttention

• Added bidirectional GroupQueryAttention support on CPU and CUDA through a backward-compatible causal attribute, with explicit handling for unsupported execution paths (#31704)
• Added a session option and Execution Provider metadata contract for using the BNHS Value KV-cache layout, with graph transformations that preserve compatibility with the existing BNSH operator schema (#32139)
• Added CPU support for attention_bias with a sliding-window KV cache, including explicit position IDs and post-eviction bias indexing (#32302)

Runtime and Performance Tools

• Fixed Compile API model serialization when output-model and custom initializer-location callbacks are used together, preventing duplicate graph fields in emitted models (#32303)
• Updated onnxruntime_perf_test to use plugin Execution Provider device allocators for generated inputs, loaded test data, and pre-allocated outputs, avoiding unnecessary per-run host/device copies (#32244)

Bug Fixes and Documentation

• Hardened FastGelu fusion to skip malformed Mul and Pow patterns (#32016)
• Added validation for in-memory external initializer references, rejecting unregistered or mismatched data before graph transformation (#32042)
• Restored the C API documentation workflow by switching the pinned Doxygen download to the official GitHub release asset (#32210)

Contributors

Thanks to our 7 contributors for this release!

@adrastogi, @apsonawane, @edgchen1, @javier-intel, @jnagi-intel, @tianleiwu, @Wayne-Ch

Release highlights were drafted with AI assistance and are subject to release-team review.

Full Changelog: v1.29.0...v1.29.1