[WIP] GQA supports per head smooth softmax #25269
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| if (use_smooth_softmax_) { | ||
| ComputeSmoothSoftmaxInplace(output_softmax + start_offset, 1, static_cast<int>(window_size), nullptr); | ||
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| if (use_smooth_softmax_ || head_sink != nullptr) { |
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Suggested change
| if (use_smooth_softmax_) { | |
| ComputeSmoothSoftmaxInplace(output_softmax + start_offset, 1, static_cast<int>(window_size), nullptr); | |
| if (use_smooth_softmax_ || head_sink != nullptr) { | |
| if (use_smooth_softmax_ || head_sink != nullptr) { |
fs-eire
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Jul 7, 2025
### Description support smooth softmax for non-FA GQA implementation This change depends on: - #25269 Work items: - [x] support smooth softmax - [x] support bias - [x] support head sink (per-head smooth softmax) The following will not be included in this PR: - support for FlashAttention - support sliding window
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Description
It is an extension of Smooth Softmax feature. The difference is that each head has a learnable smooth factor that adding to the denominator of softmax. The smooth factor s is like an extra element that joins the softmax.
The usage of the smooth factor in softmax is like the following (For Smooth Softmax, s is constant 0):
Given head_sink input, s can be looked up in head_sink for current head.
Changes in progress:
head_sink