Add large CUDA DFlash target prefill and small-query SDPA (#21628) - #21628

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Add large CUDA DFlash target prefill and small-query SDPA (#21628)#21628
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Summary:

Add a CUDA-only target_prefill method that follows the Solo target prefill path for large prompt chunks, returns final-row logits plus tapped hidden states, and shares the target KV-cache buffers with the short target_forward verifier. Keep Draft KV state independent and transfer only the final Draft sliding-window hidden rows. MLX retains its existing two-method export.

Extend the bf16 Triton split-K SDPA path from single-token decode to small query blocks through Lq=4. Preserve runtime GPU kv_len bounds, explicit per-query masks, GQA/MQA support, and CUDA Graph safety while carrying the query-row dimension through the partial softmax accumulation and reduction. This removes the long-context verifier slowdown caused by launching too few CTAs for the fixed four-token DFlash verification block.

Add exact-output runner support and a deterministic Solo-versus-DFlash benchmark covering 512/2K/8K/32K/127K prompts, fixed 512-token greedy output, structured prefill/decode/per-call metrics, acceptance statistics, peak memory, and byte-for-byte output comparison.

Reviewed By: digantdesai

Differential Revision: D114864646

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🧪 See artifacts and rendered test results at hud.pytorch.org/pr/pytorch/executorch/21628

Note: Links to docs will display an error until the docs builds have been completed.

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@meta-codesyncmeta-codesyncBot changed the title Add large CUDA DFlash target prefill and small-query SDPAAdd large CUDA DFlash target prefill and small-query SDPA (#21628)Aug 7, 2026
meta-codesyncBot pushed a commit that referenced this pull request Aug 7, 2026
@Gasoonjia@facebook-github-bot
Add large CUDA DFlash target prefill and small-query SDPA (#21628)
5b1ce33
Summary:
Add a CUDA-only `target_prefill` method that follows the Solo target prefill path for large prompt chunks, returns final-row logits plus tapped hidden states, and shares the target KV-cache buffers with the short `target_forward` verifier. Keep Draft KV state independent and transfer only the final Draft sliding-window hidden rows. MLX retains its existing two-method export.
Extend the bf16 Triton split-K SDPA path from single-token decode to small query blocks through Lq=4. Preserve runtime GPU `kv_len` bounds, explicit per-query masks, GQA/MQA support, and CUDA Graph safety while carrying the query-row dimension through the partial softmax accumulation and reduction. This removes the long-context verifier slowdown caused by launching too few CTAs for the fixed four-token DFlash verification block.
Add exact-output runner support and a deterministic Solo-versus-DFlash benchmark covering 512/2K/8K/32K/127K prompts, fixed 512-token greedy output, structured prefill/decode/per-call metrics, acceptance statistics, peak memory, and byte-for-byte output comparison.
Reviewed By: digantdesai
Differential Revision: D114864646
meta-codesyncBot pushed a commit that referenced this pull request Aug 7, 2026
@Gasoonjia@facebook-github-bot
Add large CUDA DFlash target prefill and small-query SDPA (#21628)
210656a
Summary:
Add a CUDA-only `target_prefill` method that follows the Solo target prefill path for large prompt chunks, returns final-row logits plus tapped hidden states, and shares the target KV-cache buffers with the short `target_forward` verifier. Keep Draft KV state independent and transfer only the final Draft sliding-window hidden rows. MLX retains its existing two-method export.
Extend the bf16 Triton split-K SDPA path from single-token decode to small query blocks through Lq=4. Preserve runtime GPU `kv_len` bounds, explicit per-query masks, GQA/MQA support, and CUDA Graph safety while carrying the query-row dimension through the partial softmax accumulation and reduction. This removes the long-context verifier slowdown caused by launching too few CTAs for the fixed four-token DFlash verification block.
Add exact-output runner support and a deterministic Solo-versus-DFlash benchmark covering 512/2K/8K/32K/127K prompts, fixed 512-token greedy output, structured prefill/decode/per-call metrics, acceptance statistics, peak memory, and byte-for-byte output comparison.
Reviewed By: digantdesai
Differential Revision: D114864646
meta-codesyncBot pushed a commit that referenced this pull request Aug 7, 2026
@Gasoonjia@facebook-github-bot
Add large CUDA DFlash target prefill and small-query SDPA (#21628)
4cba495
Summary:
Add a CUDA-only `target_prefill` method that follows the Solo target prefill path for large prompt chunks, returns final-row logits plus tapped hidden states, and shares the target KV-cache buffers with the short `target_forward` verifier. Keep Draft KV state independent and transfer only the final Draft sliding-window hidden rows. MLX retains its existing two-method export.
Extend the bf16 Triton split-K SDPA path from single-token decode to small query blocks through Lq=4. Preserve runtime GPU `kv_len` bounds, explicit per-query masks, GQA/MQA support, and CUDA Graph safety while carrying the query-row dimension through the partial softmax accumulation and reduction. This removes the long-context verifier slowdown caused by launching too few CTAs for the fixed four-token DFlash verification block.
Add exact-output runner support and a deterministic Solo-versus-DFlash benchmark covering 512/2K/8K/32K/127K prompts, fixed 512-token greedy output, structured prefill/decode/per-call metrics, acceptance statistics, peak memory, and byte-for-byte output comparison.
Reviewed By: digantdesai
Differential Revision: D114864646
meta-codesyncBot pushed a commit that referenced this pull request Aug 7, 2026
@Gasoonjia@facebook-github-bot
Add large CUDA DFlash target prefill and small-query SDPA (#21628)
c3f2b7b
Summary:
Add a CUDA-only `target_prefill` method that follows the Solo target prefill path for large prompt chunks, returns final-row logits plus tapped hidden states, and shares the target KV-cache buffers with the short `target_forward` verifier. Keep Draft KV state independent and transfer only the final Draft sliding-window hidden rows. MLX retains its existing two-method export.
Extend the bf16 Triton split-K SDPA path from single-token decode to small query blocks through Lq=4. Preserve runtime GPU `kv_len` bounds, explicit per-query masks, GQA/MQA support, and CUDA Graph safety while carrying the query-row dimension through the partial softmax accumulation and reduction. This removes the long-context verifier slowdown caused by launching too few CTAs for the fixed four-token DFlash verification block.
Add exact-output runner support and a deterministic Solo-versus-DFlash benchmark covering 512/2K/8K/32K/127K prompts, fixed 512-token greedy output, structured prefill/decode/per-call metrics, acceptance statistics, peak memory, and byte-for-byte output comparison.
Reviewed By: digantdesai
Differential Revision: D114864646
meta-codesyncBot pushed a commit that referenced this pull request Aug 7, 2026
@Gasoonjia@facebook-github-bot
Add large CUDA DFlash target prefill and small-query SDPA (#21628)
817e5c2
Summary:
Add a CUDA-only `target_prefill` method that follows the Solo target prefill path for large prompt chunks, returns final-row logits plus tapped hidden states, and shares the target KV-cache buffers with the short `target_forward` verifier. Keep Draft KV state independent and transfer only the final Draft sliding-window hidden rows. MLX retains its existing two-method export.
Extend the bf16 Triton split-K SDPA path from single-token decode to small query blocks through Lq=4. Preserve runtime GPU `kv_len` bounds, explicit per-query masks, GQA/MQA support, and CUDA Graph safety while carrying the query-row dimension through the partial softmax accumulation and reduction. This removes the long-context verifier slowdown caused by launching too few CTAs for the fixed four-token DFlash verification block.
Add exact-output runner support and a deterministic Solo-versus-DFlash benchmark covering 512/2K/8K/32K/127K prompts, fixed 512-token greedy output, structured prefill/decode/per-call metrics, acceptance statistics, peak memory, and byte-for-byte output comparison.
Reviewed By: digantdesai
Differential Revision: D114864646
@Gasoonjia@facebook-github-bot
Add large CUDA DFlash target prefill and small-query SDPA (#21628)
612e888
Summary:
Add a CUDA-only `target_prefill` method that follows the Solo target prefill path for large prompt chunks, returns final-row logits plus tapped hidden states, and shares the target KV-cache buffers with the short `target_forward` verifier. Keep Draft KV state independent and transfer only the final Draft sliding-window hidden rows. MLX retains its existing two-method export.
Extend the bf16 Triton split-K SDPA path from single-token decode to small query blocks through Lq=4. Preserve runtime GPU `kv_len` bounds, explicit per-query masks, GQA/MQA support, and CUDA Graph safety while carrying the query-row dimension through the partial softmax accumulation and reduction. This removes the long-context verifier slowdown caused by launching too few CTAs for the fixed four-token DFlash verification block.
Add exact-output runner support and a deterministic Solo-versus-DFlash benchmark covering 512/2K/8K/32K/127K prompts, fixed 512-token greedy output, structured prefill/decode/per-call metrics, acceptance statistics, peak memory, and byte-for-byte output comparison.
Reviewed By: digantdesai
Differential Revision: D114864646
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meta-codesyncBot merged commit 82fcf09 into mainAug 7, 2026
199 of 201 checks passed
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Add large CUDA DFlash target prefill and small-query SDPA (#21628) - #21628
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meta-codesync[bot] merged 1 commit into
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export-D114864646
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Merged
Add large CUDA DFlash target prefill and small-query SDPA (#21628)#21628
meta-codesync[bot] merged 1 commit into
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Summary:
Add a CUDA-only target_prefill method that follows the Solo target prefill path for large prompt chunks, returns final-row logits plus tapped hidden states, and shares the target KV-cache buffers with the short target_forward verifier. Keep Draft KV state independent and transfer only the final Draft sliding-window hidden rows. MLX retains its existing two-method export.
Extend the bf16 Triton split-K SDPA path from single-token decode to small query blocks through Lq=4. Preserve runtime GPU kv_len bounds, explicit per-query masks, GQA/MQA support, and CUDA Graph safety while carrying the query-row dimension through the partial softmax accumulation and reduction. This removes the long-context verifier slowdown caused by launching too few CTAs for the fixed four-token DFlash verification block.
Add exact-output runner support and a deterministic Solo-versus-DFlash benchmark covering 512/2K/8K/32K/127K prompts, fixed 512-token greedy output, structured prefill/decode/per-call metrics, acceptance statistics, peak memory, and byte-for-byte output comparison.
Reviewed By: digantdesai
Differential Revision: D114864646
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🔗 Helpful Links
🧪 See artifacts and rendered test results at hud.pytorch.org/pr/pytorch/executorch/21628
Note: Links to docs will display an error until the docs builds have been completed.
⏳ No Failures, 35 Pending
As of commit 612e888 with merge base 99924e4 (image):

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This comment was automatically generated by Dr. CI and updates every 15 minutes.
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This PR needs a release notes: label
If your change should be included in the release notes (i.e. would users of this library care about this change?), please use a label starting with release notes:. This helps us keep track and include your important work in the next release notes.
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Add large CUDA DFlash target prefill and small-query SDPAAdd large CUDA DFlash target prefill and small-query SDPA (#21628)Aug 7, 2026
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Aug 7, 2026
@Gasoonjia@facebook-github-bot
Add large CUDA DFlash target prefill and small-query SDPA (#21628)
5b1ce33
Summary:
Add a CUDA-only `target_prefill` method that follows the Solo target prefill path for large prompt chunks, returns final-row logits plus tapped hidden states, and shares the target KV-cache buffers with the short `target_forward` verifier. Keep Draft KV state independent and transfer only the final Draft sliding-window hidden rows. MLX retains its existing two-method export.
Extend the bf16 Triton split-K SDPA path from single-token decode to small query blocks through Lq=4. Preserve runtime GPU `kv_len` bounds, explicit per-query masks, GQA/MQA support, and CUDA Graph safety while carrying the query-row dimension through the partial softmax accumulation and reduction. This removes the long-context verifier slowdown caused by launching too few CTAs for the fixed four-token DFlash verification block.
Add exact-output runner support and a deterministic Solo-versus-DFlash benchmark covering 512/2K/8K/32K/127K prompts, fixed 512-token greedy output, structured prefill/decode/per-call metrics, acceptance statistics, peak memory, and byte-for-byte output comparison.
Reviewed By: digantdesai
Differential Revision: D114864646
meta-codesyncBot
pushed a commit
that referenced
this pull request
Aug 7, 2026
@Gasoonjia@facebook-github-bot
Add large CUDA DFlash target prefill and small-query SDPA (#21628)
210656a
Summary:
Add a CUDA-only `target_prefill` method that follows the Solo target prefill path for large prompt chunks, returns final-row logits plus tapped hidden states, and shares the target KV-cache buffers with the short `target_forward` verifier. Keep Draft KV state independent and transfer only the final Draft sliding-window hidden rows. MLX retains its existing two-method export.
Extend the bf16 Triton split-K SDPA path from single-token decode to small query blocks through Lq=4. Preserve runtime GPU `kv_len` bounds, explicit per-query masks, GQA/MQA support, and CUDA Graph safety while carrying the query-row dimension through the partial softmax accumulation and reduction. This removes the long-context verifier slowdown caused by launching too few CTAs for the fixed four-token DFlash verification block.
Add exact-output runner support and a deterministic Solo-versus-DFlash benchmark covering 512/2K/8K/32K/127K prompts, fixed 512-token greedy output, structured prefill/decode/per-call metrics, acceptance statistics, peak memory, and byte-for-byte output comparison.
Reviewed By: digantdesai
Differential Revision: D114864646
meta-codesyncBot
pushed a commit
that referenced
this pull request
Aug 7, 2026
@Gasoonjia@facebook-github-bot
Add large CUDA DFlash target prefill and small-query SDPA (#21628)
4cba495
Summary:
Add a CUDA-only `target_prefill` method that follows the Solo target prefill path for large prompt chunks, returns final-row logits plus tapped hidden states, and shares the target KV-cache buffers with the short `target_forward` verifier. Keep Draft KV state independent and transfer only the final Draft sliding-window hidden rows. MLX retains its existing two-method export.
Extend the bf16 Triton split-K SDPA path from single-token decode to small query blocks through Lq=4. Preserve runtime GPU `kv_len` bounds, explicit per-query masks, GQA/MQA support, and CUDA Graph safety while carrying the query-row dimension through the partial softmax accumulation and reduction. This removes the long-context verifier slowdown caused by launching too few CTAs for the fixed four-token DFlash verification block.
Add exact-output runner support and a deterministic Solo-versus-DFlash benchmark covering 512/2K/8K/32K/127K prompts, fixed 512-token greedy output, structured prefill/decode/per-call metrics, acceptance statistics, peak memory, and byte-for-byte output comparison.
Reviewed By: digantdesai
Differential Revision: D114864646
meta-codesyncBot
pushed a commit
that referenced
this pull request
Aug 7, 2026
@Gasoonjia@facebook-github-bot
Add large CUDA DFlash target prefill and small-query SDPA (#21628)
c3f2b7b
Summary:
Add a CUDA-only `target_prefill` method that follows the Solo target prefill path for large prompt chunks, returns final-row logits plus tapped hidden states, and shares the target KV-cache buffers with the short `target_forward` verifier. Keep Draft KV state independent and transfer only the final Draft sliding-window hidden rows. MLX retains its existing two-method export.
Extend the bf16 Triton split-K SDPA path from single-token decode to small query blocks through Lq=4. Preserve runtime GPU `kv_len` bounds, explicit per-query masks, GQA/MQA support, and CUDA Graph safety while carrying the query-row dimension through the partial softmax accumulation and reduction. This removes the long-context verifier slowdown caused by launching too few CTAs for the fixed four-token DFlash verification block.
Add exact-output runner support and a deterministic Solo-versus-DFlash benchmark covering 512/2K/8K/32K/127K prompts, fixed 512-token greedy output, structured prefill/decode/per-call metrics, acceptance statistics, peak memory, and byte-for-byte output comparison.
Reviewed By: digantdesai
Differential Revision: D114864646
meta-codesyncBot
pushed a commit
that referenced
this pull request
Aug 7, 2026
@Gasoonjia@facebook-github-bot
Add large CUDA DFlash target prefill and small-query SDPA (#21628)
817e5c2
Summary:
Add a CUDA-only `target_prefill` method that follows the Solo target prefill path for large prompt chunks, returns final-row logits plus tapped hidden states, and shares the target KV-cache buffers with the short `target_forward` verifier. Keep Draft KV state independent and transfer only the final Draft sliding-window hidden rows. MLX retains its existing two-method export.
Extend the bf16 Triton split-K SDPA path from single-token decode to small query blocks through Lq=4. Preserve runtime GPU `kv_len` bounds, explicit per-query masks, GQA/MQA support, and CUDA Graph safety while carrying the query-row dimension through the partial softmax accumulation and reduction. This removes the long-context verifier slowdown caused by launching too few CTAs for the fixed four-token DFlash verification block.
Add exact-output runner support and a deterministic Solo-versus-DFlash benchmark covering 512/2K/8K/32K/127K prompts, fixed 512-token greedy output, structured prefill/decode/per-call metrics, acceptance statistics, peak memory, and byte-for-byte output comparison.
Reviewed By: digantdesai
Differential Revision: D114864646
@Gasoonjia@facebook-github-bot
Add large CUDA DFlash target prefill and small-query SDPA (#21628)
612e888
Summary:
Add a CUDA-only `target_prefill` method that follows the Solo target prefill path for large prompt chunks, returns final-row logits plus tapped hidden states, and shares the target KV-cache buffers with the short `target_forward` verifier. Keep Draft KV state independent and transfer only the final Draft sliding-window hidden rows. MLX retains its existing two-method export.
Extend the bf16 Triton split-K SDPA path from single-token decode to small query blocks through Lq=4. Preserve runtime GPU `kv_len` bounds, explicit per-query masks, GQA/MQA support, and CUDA Graph safety while carrying the query-row dimension through the partial softmax accumulation and reduction. This removes the long-context verifier slowdown caused by launching too few CTAs for the fixed four-token DFlash verification block.
Add exact-output runner support and a deterministic Solo-versus-DFlash benchmark covering 512/2K/8K/32K/127K prompts, fixed 512-token greedy output, structured prefill/decode/per-call metrics, acceptance statistics, peak memory, and byte-for-byte output comparison.
Reviewed By: digantdesai
Differential Revision: D114864646
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, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Force GitHub README to respect dark mode\n(function() {\n var style = document.createElement('style');\n style.textContent = '\n .markdown-body {\n color-scheme: dark light;\n }\n .markdown-body pre { background: #161b22 !important; }\n .markdown-body code { background: rgba(110, 118, 129, 0.4) !important; }\n .markdown-body table th, .markdown-body table td { border-color: #30363d !important; }\n .markdown-body img { background: #0d1117; }\n .markdown-body blockquote { border-left-color: #8b949e; }\n .markdown-body hr { border-color: #30363d; }\n ';\n document.head.appendChild(style);\n})();", "GitHub Dark Mode README Fix");
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Skip to content
Add large CUDA DFlash target prefill and small-query SDPA (#21628) - #21628
Merged
meta-codesync[bot] merged 1 commit into
mainfrom 
export-D114864646
Aug 7, 2026
Merged
Add large CUDA DFlash target prefill and small-query SDPA (#21628)#21628
meta-codesync[bot] merged 1 commit into
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Summary:
Add a CUDA-only target_prefill method that follows the Solo target prefill path for large prompt chunks, returns final-row logits plus tapped hidden states, and shares the target KV-cache buffers with the short target_forward verifier. Keep Draft KV state independent and transfer only the final Draft sliding-window hidden rows. MLX retains its existing two-method export.
Extend the bf16 Triton split-K SDPA path from single-token decode to small query blocks through Lq=4. Preserve runtime GPU kv_len bounds, explicit per-query masks, GQA/MQA support, and CUDA Graph safety while carrying the query-row dimension through the partial softmax accumulation and reduction. This removes the long-context verifier slowdown caused by launching too few CTAs for the fixed four-token DFlash verification block.
Add exact-output runner support and a deterministic Solo-versus-DFlash benchmark covering 512/2K/8K/32K/127K prompts, fixed 512-token greedy output, structured prefill/decode/per-call metrics, acceptance statistics, peak memory, and byte-for-byte output comparison.
Reviewed By: digantdesai
Differential Revision: D114864646
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🔗 Helpful Links
🧪 See artifacts and rendered test results at hud.pytorch.org/pr/pytorch/executorch/21628
Note: Links to docs will display an error until the docs builds have been completed.
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As of commit 612e888 with merge base 99924e4 (image):

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Add large CUDA DFlash target prefill and small-query SDPAAdd large CUDA DFlash target prefill and small-query SDPA (#21628)Aug 7, 2026
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Add large CUDA DFlash target prefill and small-query SDPA (#21628)
5b1ce33
Summary:
Add a CUDA-only `target_prefill` method that follows the Solo target prefill path for large prompt chunks, returns final-row logits plus tapped hidden states, and shares the target KV-cache buffers with the short `target_forward` verifier. Keep Draft KV state independent and transfer only the final Draft sliding-window hidden rows. MLX retains its existing two-method export.
Extend the bf16 Triton split-K SDPA path from single-token decode to small query blocks through Lq=4. Preserve runtime GPU `kv_len` bounds, explicit per-query masks, GQA/MQA support, and CUDA Graph safety while carrying the query-row dimension through the partial softmax accumulation and reduction. This removes the long-context verifier slowdown caused by launching too few CTAs for the fixed four-token DFlash verification block.
Add exact-output runner support and a deterministic Solo-versus-DFlash benchmark covering 512/2K/8K/32K/127K prompts, fixed 512-token greedy output, structured prefill/decode/per-call metrics, acceptance statistics, peak memory, and byte-for-byte output comparison.
Reviewed By: digantdesai
Differential Revision: D114864646
meta-codesyncBot
pushed a commit
that referenced
this pull request
Aug 7, 2026
@Gasoonjia@facebook-github-bot
Add large CUDA DFlash target prefill and small-query SDPA (#21628)
210656a
Summary:
Add a CUDA-only `target_prefill` method that follows the Solo target prefill path for large prompt chunks, returns final-row logits plus tapped hidden states, and shares the target KV-cache buffers with the short `target_forward` verifier. Keep Draft KV state independent and transfer only the final Draft sliding-window hidden rows. MLX retains its existing two-method export.
Extend the bf16 Triton split-K SDPA path from single-token decode to small query blocks through Lq=4. Preserve runtime GPU `kv_len` bounds, explicit per-query masks, GQA/MQA support, and CUDA Graph safety while carrying the query-row dimension through the partial softmax accumulation and reduction. This removes the long-context verifier slowdown caused by launching too few CTAs for the fixed four-token DFlash verification block.
Add exact-output runner support and a deterministic Solo-versus-DFlash benchmark covering 512/2K/8K/32K/127K prompts, fixed 512-token greedy output, structured prefill/decode/per-call metrics, acceptance statistics, peak memory, and byte-for-byte output comparison.
Reviewed By: digantdesai
Differential Revision: D114864646
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@Gasoonjia@facebook-github-bot
Add large CUDA DFlash target prefill and small-query SDPA (#21628)
4cba495
Summary:
Add a CUDA-only `target_prefill` method that follows the Solo target prefill path for large prompt chunks, returns final-row logits plus tapped hidden states, and shares the target KV-cache buffers with the short `target_forward` verifier. Keep Draft KV state independent and transfer only the final Draft sliding-window hidden rows. MLX retains its existing two-method export.
Extend the bf16 Triton split-K SDPA path from single-token decode to small query blocks through Lq=4. Preserve runtime GPU `kv_len` bounds, explicit per-query masks, GQA/MQA support, and CUDA Graph safety while carrying the query-row dimension through the partial softmax accumulation and reduction. This removes the long-context verifier slowdown caused by launching too few CTAs for the fixed four-token DFlash verification block.
Add exact-output runner support and a deterministic Solo-versus-DFlash benchmark covering 512/2K/8K/32K/127K prompts, fixed 512-token greedy output, structured prefill/decode/per-call metrics, acceptance statistics, peak memory, and byte-for-byte output comparison.
Reviewed By: digantdesai
Differential Revision: D114864646
meta-codesyncBot
pushed a commit
that referenced
this pull request
Aug 7, 2026
@Gasoonjia@facebook-github-bot
Add large CUDA DFlash target prefill and small-query SDPA (#21628)
c3f2b7b
Summary:
Add a CUDA-only `target_prefill` method that follows the Solo target prefill path for large prompt chunks, returns final-row logits plus tapped hidden states, and shares the target KV-cache buffers with the short `target_forward` verifier. Keep Draft KV state independent and transfer only the final Draft sliding-window hidden rows. MLX retains its existing two-method export.
Extend the bf16 Triton split-K SDPA path from single-token decode to small query blocks through Lq=4. Preserve runtime GPU `kv_len` bounds, explicit per-query masks, GQA/MQA support, and CUDA Graph safety while carrying the query-row dimension through the partial softmax accumulation and reduction. This removes the long-context verifier slowdown caused by launching too few CTAs for the fixed four-token DFlash verification block.
Add exact-output runner support and a deterministic Solo-versus-DFlash benchmark covering 512/2K/8K/32K/127K prompts, fixed 512-token greedy output, structured prefill/decode/per-call metrics, acceptance statistics, peak memory, and byte-for-byte output comparison.
Reviewed By: digantdesai
Differential Revision: D114864646
meta-codesyncBot
pushed a commit
that referenced
this pull request
Aug 7, 2026
@Gasoonjia@facebook-github-bot
Add large CUDA DFlash target prefill and small-query SDPA (#21628)
817e5c2
Summary:
Add a CUDA-only `target_prefill` method that follows the Solo target prefill path for large prompt chunks, returns final-row logits plus tapped hidden states, and shares the target KV-cache buffers with the short `target_forward` verifier. Keep Draft KV state independent and transfer only the final Draft sliding-window hidden rows. MLX retains its existing two-method export.
Extend the bf16 Triton split-K SDPA path from single-token decode to small query blocks through Lq=4. Preserve runtime GPU `kv_len` bounds, explicit per-query masks, GQA/MQA support, and CUDA Graph safety while carrying the query-row dimension through the partial softmax accumulation and reduction. This removes the long-context verifier slowdown caused by launching too few CTAs for the fixed four-token DFlash verification block.
Add exact-output runner support and a deterministic Solo-versus-DFlash benchmark covering 512/2K/8K/32K/127K prompts, fixed 512-token greedy output, structured prefill/decode/per-call metrics, acceptance statistics, peak memory, and byte-for-byte output comparison.
Reviewed By: digantdesai
Differential Revision: D114864646
@Gasoonjia@facebook-github-bot
Add large CUDA DFlash target prefill and small-query SDPA (#21628)
612e888
Summary:
Add a CUDA-only `target_prefill` method that follows the Solo target prefill path for large prompt chunks, returns final-row logits plus tapped hidden states, and shares the target KV-cache buffers with the short `target_forward` verifier. Keep Draft KV state independent and transfer only the final Draft sliding-window hidden rows. MLX retains its existing two-method export.
Extend the bf16 Triton split-K SDPA path from single-token decode to small query blocks through Lq=4. Preserve runtime GPU `kv_len` bounds, explicit per-query masks, GQA/MQA support, and CUDA Graph safety while carrying the query-row dimension through the partial softmax accumulation and reduction. This removes the long-context verifier slowdown caused by launching too few CTAs for the fixed four-token DFlash verification block.
Add exact-output runner support and a deterministic Solo-versus-DFlash benchmark covering 512/2K/8K/32K/127K prompts, fixed 512-token greedy output, structured prefill/decode/per-call metrics, acceptance statistics, peak memory, and byte-for-byte output comparison.
Reviewed By: digantdesai
Differential Revision: D114864646
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, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Highlight search terms from Google/DuckDuckGo/Bing referrer\n(function() {\n var ref = document.referrer;\n var terms = [];\n \n if (ref.includes('google.com') || ref.includes('duckduckgo.com') || ref.includes('bing.com')) {\n var url = new URL(ref);\n var q = url.searchParams.get('q') || url.searchParams.get('p');\n if (q) {\n terms = q.split(/\\s+/).filter(function(t) { return t.length > 2; });\n }\n }\n \n if (terms.length === 0) return;\n \n var style = document.createElement('style');\n style.textContent = '.userscript-highlight { background: #fbbf24; color: #1a1a2e; padding: 1px 3px; border-radius: 2px; }';\n document.head.appendChild(style);\n \n function highlight(node) {\n if (node.nodeType === 3) { // text node\n var text = node.textContent;\n var found = false;\n terms.forEach(function(term) {\n var regex = new RegExp('(' + term.replace(/[.*+?^${}()|[\\]\\\\]/g, '\\\\') + ')', 'gi');\n if (regex.test(text)) {\n found = true;\n var frag = document.createDocumentFragment();\n var parts = text.split(regex);\n parts.forEach(function(part, i) {\n if (i % 2 === 0) {\n frag.appendChild(document.createTextNode(part));\n } else {\n var span = document.createElement('span');\n span.className = 'userscript-highlight';\n span.textContent = part;\n frag.appendChild(span);\n }\n });\n node.parentNode.replaceChild(frag, node);\n }\n });\n } else if (node.nodeType === 1 && node.childNodes) { // element\n var skipTags = ['SCRIPT', 'STYLE', 'NOSCRIPT', 'TEXTAREA', 'INPUT', 'SELECT'];\n if (!skipTags.includes(node.tagName)) {\n Array.from(node.childNodes).forEach(highlight);\n }\n }\n }\n \n highlight(document.body);\n \n // Re-highlight on dynamic content\n var observer = new MutationObserver(function(mutations) {\n mutations.forEach(function(m) {\n m.addedNodes.forEach(function(node) {\n if (node.nodeType === 1 || node.nodeType === 3) highlight(node);\n });\n });\n });\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Highlight Search Terms");
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})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

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Add large CUDA DFlash target prefill and small-query SDPA (#21628) - #21628
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Add large CUDA DFlash target prefill and small-query SDPA (#21628)#21628
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Summary:
Add a CUDA-only target_prefill method that follows the Solo target prefill path for large prompt chunks, returns final-row logits plus tapped hidden states, and shares the target KV-cache buffers with the short target_forward verifier. Keep Draft KV state independent and transfer only the final Draft sliding-window hidden rows. MLX retains its existing two-method export.
Extend the bf16 Triton split-K SDPA path from single-token decode to small query blocks through Lq=4. Preserve runtime GPU kv_len bounds, explicit per-query masks, GQA/MQA support, and CUDA Graph safety while carrying the query-row dimension through the partial softmax accumulation and reduction. This removes the long-context verifier slowdown caused by launching too few CTAs for the fixed four-token DFlash verification block.
Add exact-output runner support and a deterministic Solo-versus-DFlash benchmark covering 512/2K/8K/32K/127K prompts, fixed 512-token greedy output, structured prefill/decode/per-call metrics, acceptance statistics, peak memory, and byte-for-byte output comparison.
Reviewed By: digantdesai
Differential Revision: D114864646
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🔗 Helpful Links
🧪 See artifacts and rendered test results at hud.pytorch.org/pr/pytorch/executorch/21628
Note: Links to docs will display an error until the docs builds have been completed.
⏳ No Failures, 35 Pending
As of commit 612e888 with merge base 99924e4 (image):

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This comment was automatically generated by Dr. CI and updates every 15 minutes.
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This PR needs a release notes: label
If your change should be included in the release notes (i.e. would users of this library care about this change?), please use a label starting with release notes:. This helps us keep track and include your important work in the next release notes.
To add a label, you can comment to pytorchbot, for example
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https://github.com/pytorch/pytorch/wiki/PyTorch-AutoLabel-Bot#why-categorize-for-release-notes-and-how-does-it-work.
@meta-codesyncmeta-codesyncBot
changed the title
Add large CUDA DFlash target prefill and small-query SDPAAdd large CUDA DFlash target prefill and small-query SDPA (#21628)Aug 7, 2026
meta-codesyncBot
pushed a commit
that referenced
this pull request
Aug 7, 2026
@Gasoonjia@facebook-github-bot
Add large CUDA DFlash target prefill and small-query SDPA (#21628)
5b1ce33
Summary:
Add a CUDA-only `target_prefill` method that follows the Solo target prefill path for large prompt chunks, returns final-row logits plus tapped hidden states, and shares the target KV-cache buffers with the short `target_forward` verifier. Keep Draft KV state independent and transfer only the final Draft sliding-window hidden rows. MLX retains its existing two-method export.
Extend the bf16 Triton split-K SDPA path from single-token decode to small query blocks through Lq=4. Preserve runtime GPU `kv_len` bounds, explicit per-query masks, GQA/MQA support, and CUDA Graph safety while carrying the query-row dimension through the partial softmax accumulation and reduction. This removes the long-context verifier slowdown caused by launching too few CTAs for the fixed four-token DFlash verification block.
Add exact-output runner support and a deterministic Solo-versus-DFlash benchmark covering 512/2K/8K/32K/127K prompts, fixed 512-token greedy output, structured prefill/decode/per-call metrics, acceptance statistics, peak memory, and byte-for-byte output comparison.
Reviewed By: digantdesai
Differential Revision: D114864646
meta-codesyncBot
pushed a commit
that referenced
this pull request
Aug 7, 2026
@Gasoonjia@facebook-github-bot
Add large CUDA DFlash target prefill and small-query SDPA (#21628)
210656a
Summary:
Add a CUDA-only `target_prefill` method that follows the Solo target prefill path for large prompt chunks, returns final-row logits plus tapped hidden states, and shares the target KV-cache buffers with the short `target_forward` verifier. Keep Draft KV state independent and transfer only the final Draft sliding-window hidden rows. MLX retains its existing two-method export.
Extend the bf16 Triton split-K SDPA path from single-token decode to small query blocks through Lq=4. Preserve runtime GPU `kv_len` bounds, explicit per-query masks, GQA/MQA support, and CUDA Graph safety while carrying the query-row dimension through the partial softmax accumulation and reduction. This removes the long-context verifier slowdown caused by launching too few CTAs for the fixed four-token DFlash verification block.
Add exact-output runner support and a deterministic Solo-versus-DFlash benchmark covering 512/2K/8K/32K/127K prompts, fixed 512-token greedy output, structured prefill/decode/per-call metrics, acceptance statistics, peak memory, and byte-for-byte output comparison.
Reviewed By: digantdesai
Differential Revision: D114864646
meta-codesyncBot
pushed a commit
that referenced
this pull request
Aug 7, 2026
@Gasoonjia@facebook-github-bot
Add large CUDA DFlash target prefill and small-query SDPA (#21628)
4cba495
Summary:
Add a CUDA-only `target_prefill` method that follows the Solo target prefill path for large prompt chunks, returns final-row logits plus tapped hidden states, and shares the target KV-cache buffers with the short `target_forward` verifier. Keep Draft KV state independent and transfer only the final Draft sliding-window hidden rows. MLX retains its existing two-method export.
Extend the bf16 Triton split-K SDPA path from single-token decode to small query blocks through Lq=4. Preserve runtime GPU `kv_len` bounds, explicit per-query masks, GQA/MQA support, and CUDA Graph safety while carrying the query-row dimension through the partial softmax accumulation and reduction. This removes the long-context verifier slowdown caused by launching too few CTAs for the fixed four-token DFlash verification block.
Add exact-output runner support and a deterministic Solo-versus-DFlash benchmark covering 512/2K/8K/32K/127K prompts, fixed 512-token greedy output, structured prefill/decode/per-call metrics, acceptance statistics, peak memory, and byte-for-byte output comparison.
Reviewed By: digantdesai
Differential Revision: D114864646
meta-codesyncBot
pushed a commit
that referenced
this pull request
Aug 7, 2026
@Gasoonjia@facebook-github-bot
Add large CUDA DFlash target prefill and small-query SDPA (#21628)
c3f2b7b
Summary:
Add a CUDA-only `target_prefill` method that follows the Solo target prefill path for large prompt chunks, returns final-row logits plus tapped hidden states, and shares the target KV-cache buffers with the short `target_forward` verifier. Keep Draft KV state independent and transfer only the final Draft sliding-window hidden rows. MLX retains its existing two-method export.
Extend the bf16 Triton split-K SDPA path from single-token decode to small query blocks through Lq=4. Preserve runtime GPU `kv_len` bounds, explicit per-query masks, GQA/MQA support, and CUDA Graph safety while carrying the query-row dimension through the partial softmax accumulation and reduction. This removes the long-context verifier slowdown caused by launching too few CTAs for the fixed four-token DFlash verification block.
Add exact-output runner support and a deterministic Solo-versus-DFlash benchmark covering 512/2K/8K/32K/127K prompts, fixed 512-token greedy output, structured prefill/decode/per-call metrics, acceptance statistics, peak memory, and byte-for-byte output comparison.
Reviewed By: digantdesai
Differential Revision: D114864646
meta-codesyncBot
pushed a commit
that referenced
this pull request
Aug 7, 2026
@Gasoonjia@facebook-github-bot
Add large CUDA DFlash target prefill and small-query SDPA (#21628)
817e5c2
Summary:
Add a CUDA-only `target_prefill` method that follows the Solo target prefill path for large prompt chunks, returns final-row logits plus tapped hidden states, and shares the target KV-cache buffers with the short `target_forward` verifier. Keep Draft KV state independent and transfer only the final Draft sliding-window hidden rows. MLX retains its existing two-method export.
Extend the bf16 Triton split-K SDPA path from single-token decode to small query blocks through Lq=4. Preserve runtime GPU `kv_len` bounds, explicit per-query masks, GQA/MQA support, and CUDA Graph safety while carrying the query-row dimension through the partial softmax accumulation and reduction. This removes the long-context verifier slowdown caused by launching too few CTAs for the fixed four-token DFlash verification block.
Add exact-output runner support and a deterministic Solo-versus-DFlash benchmark covering 512/2K/8K/32K/127K prompts, fixed 512-token greedy output, structured prefill/decode/per-call metrics, acceptance statistics, peak memory, and byte-for-byte output comparison.
Reviewed By: digantdesai
Differential Revision: D114864646
@Gasoonjia@facebook-github-bot
Add large CUDA DFlash target prefill and small-query SDPA (#21628)
612e888
Summary:
Add a CUDA-only `target_prefill` method that follows the Solo target prefill path for large prompt chunks, returns final-row logits plus tapped hidden states, and shares the target KV-cache buffers with the short `target_forward` verifier. Keep Draft KV state independent and transfer only the final Draft sliding-window hidden rows. MLX retains its existing two-method export.
Extend the bf16 Triton split-K SDPA path from single-token decode to small query blocks through Lq=4. Preserve runtime GPU `kv_len` bounds, explicit per-query masks, GQA/MQA support, and CUDA Graph safety while carrying the query-row dimension through the partial softmax accumulation and reduction. This removes the long-context verifier slowdown caused by launching too few CTAs for the fixed four-token DFlash verification block.
Add exact-output runner support and a deterministic Solo-versus-DFlash benchmark covering 512/2K/8K/32K/127K prompts, fixed 512-token greedy output, structured prefill/decode/per-call metrics, acceptance statistics, peak memory, and byte-for-byte output comparison.
Reviewed By: digantdesai
Differential Revision: D114864646
@meta-codesync
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merged commit 82fcf09
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199 of 201 checks passed

@meta-codesync
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mentioned this pull request
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 Merged

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, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Strip utm_, fbclid, gclid, etc. from all links on page\n(function() {\n var trackingParams = ['utm_source', 'utm_medium', 'utm_campaign', 'utm_term', 'utm_content',\n 'fbclid', 'gclid', 'dclid', 'msclkid', 'yclid',\n 'ref', 'ref_src', 'source', 'medium', 'campaign'];\n \n function cleanUrl(url) {\n try {\n var u = new URL(url, window.location.origin);\n var changed = false;\n trackingParams.forEach(function(p) {\n if (u.searchParams.has(p)) {\n u.searchParams.delete(p);\n changed = true;\n }\n });\n return changed ? u.toString() : url;\n } catch (e) {\n return url;\n }\n }\n \n function cleanLinks() {\n document.querySelectorAll('a[href]').forEach(function(a) {\n var clean = cleanUrl(a.href);\n if (clean !== a.href) a.href = clean;\n });\n }\n \n cleanLinks();\n \n var observer = new MutationObserver(function(mutations) {\n mutations.forEach(function(m) {\n m.addedNodes.forEach(function(node) {\n if (node.nodeType === 1) {\n if (node.tagName === 'A') cleanLinks();\n node.querySelectorAll('a[href]').forEach(function(a) {\n var clean = cleanUrl(a.href);\n if (clean !== a.href) a.href = clean;\n });\n }\n });\n });\n });\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Remove Tracking Parameters from Links");
}
} catch(__e) { console.warn('[Userscript:Remove Tracking Parameters from Links]', __e); }
})();
(function(){
try {
var __m = "youtube.com";
var __re = new RegExp('^' + "youtube\\.com" + '

Skip to content
Add large CUDA DFlash target prefill and small-query SDPA (#21628) - #21628
Merged
meta-codesync[bot] merged 1 commit into
mainfrom 
export-D114864646
Aug 7, 2026
Merged
Add large CUDA DFlash target prefill and small-query SDPA (#21628)#21628
meta-codesync[bot] merged 1 commit into
mainfrom 
export-D114864646
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edited by meta-codesync
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Summary:
Add a CUDA-only target_prefill method that follows the Solo target prefill path for large prompt chunks, returns final-row logits plus tapped hidden states, and shares the target KV-cache buffers with the short target_forward verifier. Keep Draft KV state independent and transfer only the final Draft sliding-window hidden rows. MLX retains its existing two-method export.
Extend the bf16 Triton split-K SDPA path from single-token decode to small query blocks through Lq=4. Preserve runtime GPU kv_len bounds, explicit per-query masks, GQA/MQA support, and CUDA Graph safety while carrying the query-row dimension through the partial softmax accumulation and reduction. This removes the long-context verifier slowdown caused by launching too few CTAs for the fixed four-token DFlash verification block.
Add exact-output runner support and a deterministic Solo-versus-DFlash benchmark covering 512/2K/8K/32K/127K prompts, fixed 512-token greedy output, structured prefill/decode/per-call metrics, acceptance statistics, peak memory, and byte-for-byte output comparison.
Reviewed By: digantdesai
Differential Revision: D114864646
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🔗 Helpful Links
🧪 See artifacts and rendered test results at hud.pytorch.org/pr/pytorch/executorch/21628
Note: Links to docs will display an error until the docs builds have been completed.
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Add large CUDA DFlash target prefill and small-query SDPA (#21628)
5b1ce33
Summary:
Add a CUDA-only `target_prefill` method that follows the Solo target prefill path for large prompt chunks, returns final-row logits plus tapped hidden states, and shares the target KV-cache buffers with the short `target_forward` verifier. Keep Draft KV state independent and transfer only the final Draft sliding-window hidden rows. MLX retains its existing two-method export.
Extend the bf16 Triton split-K SDPA path from single-token decode to small query blocks through Lq=4. Preserve runtime GPU `kv_len` bounds, explicit per-query masks, GQA/MQA support, and CUDA Graph safety while carrying the query-row dimension through the partial softmax accumulation and reduction. This removes the long-context verifier slowdown caused by launching too few CTAs for the fixed four-token DFlash verification block.
Add exact-output runner support and a deterministic Solo-versus-DFlash benchmark covering 512/2K/8K/32K/127K prompts, fixed 512-token greedy output, structured prefill/decode/per-call metrics, acceptance statistics, peak memory, and byte-for-byte output comparison.
Reviewed By: digantdesai
Differential Revision: D114864646
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Add large CUDA DFlash target prefill and small-query SDPA (#21628)
210656a
Summary:
Add a CUDA-only `target_prefill` method that follows the Solo target prefill path for large prompt chunks, returns final-row logits plus tapped hidden states, and shares the target KV-cache buffers with the short `target_forward` verifier. Keep Draft KV state independent and transfer only the final Draft sliding-window hidden rows. MLX retains its existing two-method export.
Extend the bf16 Triton split-K SDPA path from single-token decode to small query blocks through Lq=4. Preserve runtime GPU `kv_len` bounds, explicit per-query masks, GQA/MQA support, and CUDA Graph safety while carrying the query-row dimension through the partial softmax accumulation and reduction. This removes the long-context verifier slowdown caused by launching too few CTAs for the fixed four-token DFlash verification block.
Add exact-output runner support and a deterministic Solo-versus-DFlash benchmark covering 512/2K/8K/32K/127K prompts, fixed 512-token greedy output, structured prefill/decode/per-call metrics, acceptance statistics, peak memory, and byte-for-byte output comparison.
Reviewed By: digantdesai
Differential Revision: D114864646
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Add large CUDA DFlash target prefill and small-query SDPA (#21628)
4cba495
Summary:
Add a CUDA-only `target_prefill` method that follows the Solo target prefill path for large prompt chunks, returns final-row logits plus tapped hidden states, and shares the target KV-cache buffers with the short `target_forward` verifier. Keep Draft KV state independent and transfer only the final Draft sliding-window hidden rows. MLX retains its existing two-method export.
Extend the bf16 Triton split-K SDPA path from single-token decode to small query blocks through Lq=4. Preserve runtime GPU `kv_len` bounds, explicit per-query masks, GQA/MQA support, and CUDA Graph safety while carrying the query-row dimension through the partial softmax accumulation and reduction. This removes the long-context verifier slowdown caused by launching too few CTAs for the fixed four-token DFlash verification block.
Add exact-output runner support and a deterministic Solo-versus-DFlash benchmark covering 512/2K/8K/32K/127K prompts, fixed 512-token greedy output, structured prefill/decode/per-call metrics, acceptance statistics, peak memory, and byte-for-byte output comparison.
Reviewed By: digantdesai
Differential Revision: D114864646
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@Gasoonjia@facebook-github-bot
Add large CUDA DFlash target prefill and small-query SDPA (#21628)
c3f2b7b
Summary:
Add a CUDA-only `target_prefill` method that follows the Solo target prefill path for large prompt chunks, returns final-row logits plus tapped hidden states, and shares the target KV-cache buffers with the short `target_forward` verifier. Keep Draft KV state independent and transfer only the final Draft sliding-window hidden rows. MLX retains its existing two-method export.
Extend the bf16 Triton split-K SDPA path from single-token decode to small query blocks through Lq=4. Preserve runtime GPU `kv_len` bounds, explicit per-query masks, GQA/MQA support, and CUDA Graph safety while carrying the query-row dimension through the partial softmax accumulation and reduction. This removes the long-context verifier slowdown caused by launching too few CTAs for the fixed four-token DFlash verification block.
Add exact-output runner support and a deterministic Solo-versus-DFlash benchmark covering 512/2K/8K/32K/127K prompts, fixed 512-token greedy output, structured prefill/decode/per-call metrics, acceptance statistics, peak memory, and byte-for-byte output comparison.
Reviewed By: digantdesai
Differential Revision: D114864646
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Add large CUDA DFlash target prefill and small-query SDPA (#21628)
817e5c2
Summary:
Add a CUDA-only `target_prefill` method that follows the Solo target prefill path for large prompt chunks, returns final-row logits plus tapped hidden states, and shares the target KV-cache buffers with the short `target_forward` verifier. Keep Draft KV state independent and transfer only the final Draft sliding-window hidden rows. MLX retains its existing two-method export.
Extend the bf16 Triton split-K SDPA path from single-token decode to small query blocks through Lq=4. Preserve runtime GPU `kv_len` bounds, explicit per-query masks, GQA/MQA support, and CUDA Graph safety while carrying the query-row dimension through the partial softmax accumulation and reduction. This removes the long-context verifier slowdown caused by launching too few CTAs for the fixed four-token DFlash verification block.
Add exact-output runner support and a deterministic Solo-versus-DFlash benchmark covering 512/2K/8K/32K/127K prompts, fixed 512-token greedy output, structured prefill/decode/per-call metrics, acceptance statistics, peak memory, and byte-for-byte output comparison.
Reviewed By: digantdesai
Differential Revision: D114864646
@Gasoonjia@facebook-github-bot
Add large CUDA DFlash target prefill and small-query SDPA (#21628)
612e888
Summary:
Add a CUDA-only `target_prefill` method that follows the Solo target prefill path for large prompt chunks, returns final-row logits plus tapped hidden states, and shares the target KV-cache buffers with the short `target_forward` verifier. Keep Draft KV state independent and transfer only the final Draft sliding-window hidden rows. MLX retains its existing two-method export.
Extend the bf16 Triton split-K SDPA path from single-token decode to small query blocks through Lq=4. Preserve runtime GPU `kv_len` bounds, explicit per-query masks, GQA/MQA support, and CUDA Graph safety while carrying the query-row dimension through the partial softmax accumulation and reduction. This removes the long-context verifier slowdown caused by launching too few CTAs for the fixed four-token DFlash verification block.
Add exact-output runner support and a deterministic Solo-versus-DFlash benchmark covering 512/2K/8K/32K/127K prompts, fixed 512-token greedy output, structured prefill/decode/per-call metrics, acceptance statistics, peak memory, and byte-for-byte output comparison.
Reviewed By: digantdesai
Differential Revision: D114864646
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, 'i');
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injectUserscript("// Auto-enable theater mode on YouTube\n(function() {\n function tryTheater() {\n var btn = document.querySelector('button[aria-label=\"Theater mode\"], ytd-player #player button[title=\"Theater mode\"]');\n if (btn && !btn.classList.contains('activated')) {\n btn.click();\n }\n }\n \n // Try immediately\n tryTheater();\n \n // Try after navigation (SPA)\n var lastUrl = location.href;\n setInterval(function() {\n if (location.href !== lastUrl) {\n lastUrl = location.href;\n setTimeout(tryTheater, 500);\n }\n }, 1000);\n \n // Also try on player load\n var observer = new MutationObserver(tryTheater);\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "YouTube Theater Mode Default");
}
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})();
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try {
var __m = "*";
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Add large CUDA DFlash target prefill and small-query SDPA (#21628) - #21628
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Add large CUDA DFlash target prefill and small-query SDPA (#21628)#21628
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Summary:
Add a CUDA-only target_prefill method that follows the Solo target prefill path for large prompt chunks, returns final-row logits plus tapped hidden states, and shares the target KV-cache buffers with the short target_forward verifier. Keep Draft KV state independent and transfer only the final Draft sliding-window hidden rows. MLX retains its existing two-method export.
Extend the bf16 Triton split-K SDPA path from single-token decode to small query blocks through Lq=4. Preserve runtime GPU kv_len bounds, explicit per-query masks, GQA/MQA support, and CUDA Graph safety while carrying the query-row dimension through the partial softmax accumulation and reduction. This removes the long-context verifier slowdown caused by launching too few CTAs for the fixed four-token DFlash verification block.
Add exact-output runner support and a deterministic Solo-versus-DFlash benchmark covering 512/2K/8K/32K/127K prompts, fixed 512-token greedy output, structured prefill/decode/per-call metrics, acceptance statistics, peak memory, and byte-for-byte output comparison.
Reviewed By: digantdesai
Differential Revision: D114864646
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🔗 Helpful Links
🧪 See artifacts and rendered test results at hud.pytorch.org/pr/pytorch/executorch/21628
Note: Links to docs will display an error until the docs builds have been completed.
⏳ No Failures, 35 Pending
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Add large CUDA DFlash target prefill and small-query SDPAAdd large CUDA DFlash target prefill and small-query SDPA (#21628)Aug 7, 2026
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@Gasoonjia@facebook-github-bot
Add large CUDA DFlash target prefill and small-query SDPA (#21628)
5b1ce33
Summary:
Add a CUDA-only `target_prefill` method that follows the Solo target prefill path for large prompt chunks, returns final-row logits plus tapped hidden states, and shares the target KV-cache buffers with the short `target_forward` verifier. Keep Draft KV state independent and transfer only the final Draft sliding-window hidden rows. MLX retains its existing two-method export.
Extend the bf16 Triton split-K SDPA path from single-token decode to small query blocks through Lq=4. Preserve runtime GPU `kv_len` bounds, explicit per-query masks, GQA/MQA support, and CUDA Graph safety while carrying the query-row dimension through the partial softmax accumulation and reduction. This removes the long-context verifier slowdown caused by launching too few CTAs for the fixed four-token DFlash verification block.
Add exact-output runner support and a deterministic Solo-versus-DFlash benchmark covering 512/2K/8K/32K/127K prompts, fixed 512-token greedy output, structured prefill/decode/per-call metrics, acceptance statistics, peak memory, and byte-for-byte output comparison.
Reviewed By: digantdesai
Differential Revision: D114864646
meta-codesyncBot
pushed a commit
that referenced
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@Gasoonjia@facebook-github-bot
Add large CUDA DFlash target prefill and small-query SDPA (#21628)
210656a
Summary:
Add a CUDA-only `target_prefill` method that follows the Solo target prefill path for large prompt chunks, returns final-row logits plus tapped hidden states, and shares the target KV-cache buffers with the short `target_forward` verifier. Keep Draft KV state independent and transfer only the final Draft sliding-window hidden rows. MLX retains its existing two-method export.
Extend the bf16 Triton split-K SDPA path from single-token decode to small query blocks through Lq=4. Preserve runtime GPU `kv_len` bounds, explicit per-query masks, GQA/MQA support, and CUDA Graph safety while carrying the query-row dimension through the partial softmax accumulation and reduction. This removes the long-context verifier slowdown caused by launching too few CTAs for the fixed four-token DFlash verification block.
Add exact-output runner support and a deterministic Solo-versus-DFlash benchmark covering 512/2K/8K/32K/127K prompts, fixed 512-token greedy output, structured prefill/decode/per-call metrics, acceptance statistics, peak memory, and byte-for-byte output comparison.
Reviewed By: digantdesai
Differential Revision: D114864646
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@Gasoonjia@facebook-github-bot
Add large CUDA DFlash target prefill and small-query SDPA (#21628)
4cba495
Summary:
Add a CUDA-only `target_prefill` method that follows the Solo target prefill path for large prompt chunks, returns final-row logits plus tapped hidden states, and shares the target KV-cache buffers with the short `target_forward` verifier. Keep Draft KV state independent and transfer only the final Draft sliding-window hidden rows. MLX retains its existing two-method export.
Extend the bf16 Triton split-K SDPA path from single-token decode to small query blocks through Lq=4. Preserve runtime GPU `kv_len` bounds, explicit per-query masks, GQA/MQA support, and CUDA Graph safety while carrying the query-row dimension through the partial softmax accumulation and reduction. This removes the long-context verifier slowdown caused by launching too few CTAs for the fixed four-token DFlash verification block.
Add exact-output runner support and a deterministic Solo-versus-DFlash benchmark covering 512/2K/8K/32K/127K prompts, fixed 512-token greedy output, structured prefill/decode/per-call metrics, acceptance statistics, peak memory, and byte-for-byte output comparison.
Reviewed By: digantdesai
Differential Revision: D114864646
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that referenced
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@Gasoonjia@facebook-github-bot
Add large CUDA DFlash target prefill and small-query SDPA (#21628)
c3f2b7b
Summary:
Add a CUDA-only `target_prefill` method that follows the Solo target prefill path for large prompt chunks, returns final-row logits plus tapped hidden states, and shares the target KV-cache buffers with the short `target_forward` verifier. Keep Draft KV state independent and transfer only the final Draft sliding-window hidden rows. MLX retains its existing two-method export.
Extend the bf16 Triton split-K SDPA path from single-token decode to small query blocks through Lq=4. Preserve runtime GPU `kv_len` bounds, explicit per-query masks, GQA/MQA support, and CUDA Graph safety while carrying the query-row dimension through the partial softmax accumulation and reduction. This removes the long-context verifier slowdown caused by launching too few CTAs for the fixed four-token DFlash verification block.
Add exact-output runner support and a deterministic Solo-versus-DFlash benchmark covering 512/2K/8K/32K/127K prompts, fixed 512-token greedy output, structured prefill/decode/per-call metrics, acceptance statistics, peak memory, and byte-for-byte output comparison.
Reviewed By: digantdesai
Differential Revision: D114864646
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@Gasoonjia@facebook-github-bot
Add large CUDA DFlash target prefill and small-query SDPA (#21628)
817e5c2
Summary:
Add a CUDA-only `target_prefill` method that follows the Solo target prefill path for large prompt chunks, returns final-row logits plus tapped hidden states, and shares the target KV-cache buffers with the short `target_forward` verifier. Keep Draft KV state independent and transfer only the final Draft sliding-window hidden rows. MLX retains its existing two-method export.
Extend the bf16 Triton split-K SDPA path from single-token decode to small query blocks through Lq=4. Preserve runtime GPU `kv_len` bounds, explicit per-query masks, GQA/MQA support, and CUDA Graph safety while carrying the query-row dimension through the partial softmax accumulation and reduction. This removes the long-context verifier slowdown caused by launching too few CTAs for the fixed four-token DFlash verification block.
Add exact-output runner support and a deterministic Solo-versus-DFlash benchmark covering 512/2K/8K/32K/127K prompts, fixed 512-token greedy output, structured prefill/decode/per-call metrics, acceptance statistics, peak memory, and byte-for-byte output comparison.
Reviewed By: digantdesai
Differential Revision: D114864646
@Gasoonjia@facebook-github-bot
Add large CUDA DFlash target prefill and small-query SDPA (#21628)
612e888
Summary:
Add a CUDA-only `target_prefill` method that follows the Solo target prefill path for large prompt chunks, returns final-row logits plus tapped hidden states, and shares the target KV-cache buffers with the short `target_forward` verifier. Keep Draft KV state independent and transfer only the final Draft sliding-window hidden rows. MLX retains its existing two-method export.
Extend the bf16 Triton split-K SDPA path from single-token decode to small query blocks through Lq=4. Preserve runtime GPU `kv_len` bounds, explicit per-query masks, GQA/MQA support, and CUDA Graph safety while carrying the query-row dimension through the partial softmax accumulation and reduction. This removes the long-context verifier slowdown caused by launching too few CTAs for the fixed four-token DFlash verification block.
Add exact-output runner support and a deterministic Solo-versus-DFlash benchmark covering 512/2K/8K/32K/127K prompts, fixed 512-token greedy output, structured prefill/decode/per-call metrics, acceptance statistics, peak memory, and byte-for-byte output comparison.
Reviewed By: digantdesai
Differential Revision: D114864646
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, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Remove or un-stick sticky/fixed headers that block content\n(function() {\n function unstick() {\n document.querySelectorAll('header, nav, [role=\"banner\"], .header, .navbar, .sticky, .fixed-top, [style*=\"position: fixed\"], [style*=\"position:sticky\"]').forEach(function(el) {\n if (el.style.position === 'fixed' || el.style.position === 'sticky' || \n getComputedStyle(el).position === 'fixed' || getComputedStyle(el).position === 'sticky') {\n el.style.position = 'static';\n el.style.top = 'auto';\n el.style.zIndex = 'auto';\n }\n });\n }\n \n unstick();\n \n var observer = new MutationObserver(unstick);\n observer.observe(document.body, { childList: true, subtree: true, attributes: true, attributeFilter: ['style', 'class'] });\n})();", "Kill Sticky Headers");
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})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

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Add large CUDA DFlash target prefill and small-query SDPA (#21628) - #21628
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Merged
Add large CUDA DFlash target prefill and small-query SDPA (#21628)#21628
meta-codesync[bot] merged 1 commit into
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Summary:
Add a CUDA-only target_prefill method that follows the Solo target prefill path for large prompt chunks, returns final-row logits plus tapped hidden states, and shares the target KV-cache buffers with the short target_forward verifier. Keep Draft KV state independent and transfer only the final Draft sliding-window hidden rows. MLX retains its existing two-method export.
Extend the bf16 Triton split-K SDPA path from single-token decode to small query blocks through Lq=4. Preserve runtime GPU kv_len bounds, explicit per-query masks, GQA/MQA support, and CUDA Graph safety while carrying the query-row dimension through the partial softmax accumulation and reduction. This removes the long-context verifier slowdown caused by launching too few CTAs for the fixed four-token DFlash verification block.
Add exact-output runner support and a deterministic Solo-versus-DFlash benchmark covering 512/2K/8K/32K/127K prompts, fixed 512-token greedy output, structured prefill/decode/per-call metrics, acceptance statistics, peak memory, and byte-for-byte output comparison.
Reviewed By: digantdesai
Differential Revision: D114864646
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🔗 Helpful Links
🧪 See artifacts and rendered test results at hud.pytorch.org/pr/pytorch/executorch/21628
Note: Links to docs will display an error until the docs builds have been completed.
⏳ No Failures, 35 Pending
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@Gasoonjia@facebook-github-bot
Add large CUDA DFlash target prefill and small-query SDPA (#21628)
5b1ce33
Summary:
Add a CUDA-only `target_prefill` method that follows the Solo target prefill path for large prompt chunks, returns final-row logits plus tapped hidden states, and shares the target KV-cache buffers with the short `target_forward` verifier. Keep Draft KV state independent and transfer only the final Draft sliding-window hidden rows. MLX retains its existing two-method export.
Extend the bf16 Triton split-K SDPA path from single-token decode to small query blocks through Lq=4. Preserve runtime GPU `kv_len` bounds, explicit per-query masks, GQA/MQA support, and CUDA Graph safety while carrying the query-row dimension through the partial softmax accumulation and reduction. This removes the long-context verifier slowdown caused by launching too few CTAs for the fixed four-token DFlash verification block.
Add exact-output runner support and a deterministic Solo-versus-DFlash benchmark covering 512/2K/8K/32K/127K prompts, fixed 512-token greedy output, structured prefill/decode/per-call metrics, acceptance statistics, peak memory, and byte-for-byte output comparison.
Reviewed By: digantdesai
Differential Revision: D114864646
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@Gasoonjia@facebook-github-bot
Add large CUDA DFlash target prefill and small-query SDPA (#21628)
210656a
Summary:
Add a CUDA-only `target_prefill` method that follows the Solo target prefill path for large prompt chunks, returns final-row logits plus tapped hidden states, and shares the target KV-cache buffers with the short `target_forward` verifier. Keep Draft KV state independent and transfer only the final Draft sliding-window hidden rows. MLX retains its existing two-method export.
Extend the bf16 Triton split-K SDPA path from single-token decode to small query blocks through Lq=4. Preserve runtime GPU `kv_len` bounds, explicit per-query masks, GQA/MQA support, and CUDA Graph safety while carrying the query-row dimension through the partial softmax accumulation and reduction. This removes the long-context verifier slowdown caused by launching too few CTAs for the fixed four-token DFlash verification block.
Add exact-output runner support and a deterministic Solo-versus-DFlash benchmark covering 512/2K/8K/32K/127K prompts, fixed 512-token greedy output, structured prefill/decode/per-call metrics, acceptance statistics, peak memory, and byte-for-byte output comparison.
Reviewed By: digantdesai
Differential Revision: D114864646
meta-codesyncBot
pushed a commit
that referenced
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@Gasoonjia@facebook-github-bot
Add large CUDA DFlash target prefill and small-query SDPA (#21628)
4cba495
Summary:
Add a CUDA-only `target_prefill` method that follows the Solo target prefill path for large prompt chunks, returns final-row logits plus tapped hidden states, and shares the target KV-cache buffers with the short `target_forward` verifier. Keep Draft KV state independent and transfer only the final Draft sliding-window hidden rows. MLX retains its existing two-method export.
Extend the bf16 Triton split-K SDPA path from single-token decode to small query blocks through Lq=4. Preserve runtime GPU `kv_len` bounds, explicit per-query masks, GQA/MQA support, and CUDA Graph safety while carrying the query-row dimension through the partial softmax accumulation and reduction. This removes the long-context verifier slowdown caused by launching too few CTAs for the fixed four-token DFlash verification block.
Add exact-output runner support and a deterministic Solo-versus-DFlash benchmark covering 512/2K/8K/32K/127K prompts, fixed 512-token greedy output, structured prefill/decode/per-call metrics, acceptance statistics, peak memory, and byte-for-byte output comparison.
Reviewed By: digantdesai
Differential Revision: D114864646
meta-codesyncBot
pushed a commit
that referenced
this pull request
Aug 7, 2026
@Gasoonjia@facebook-github-bot
Add large CUDA DFlash target prefill and small-query SDPA (#21628)
c3f2b7b
Summary:
Add a CUDA-only `target_prefill` method that follows the Solo target prefill path for large prompt chunks, returns final-row logits plus tapped hidden states, and shares the target KV-cache buffers with the short `target_forward` verifier. Keep Draft KV state independent and transfer only the final Draft sliding-window hidden rows. MLX retains its existing two-method export.
Extend the bf16 Triton split-K SDPA path from single-token decode to small query blocks through Lq=4. Preserve runtime GPU `kv_len` bounds, explicit per-query masks, GQA/MQA support, and CUDA Graph safety while carrying the query-row dimension through the partial softmax accumulation and reduction. This removes the long-context verifier slowdown caused by launching too few CTAs for the fixed four-token DFlash verification block.
Add exact-output runner support and a deterministic Solo-versus-DFlash benchmark covering 512/2K/8K/32K/127K prompts, fixed 512-token greedy output, structured prefill/decode/per-call metrics, acceptance statistics, peak memory, and byte-for-byte output comparison.
Reviewed By: digantdesai
Differential Revision: D114864646
meta-codesyncBot
pushed a commit
that referenced
this pull request
Aug 7, 2026
@Gasoonjia@facebook-github-bot
Add large CUDA DFlash target prefill and small-query SDPA (#21628)
817e5c2
Summary:
Add a CUDA-only `target_prefill` method that follows the Solo target prefill path for large prompt chunks, returns final-row logits plus tapped hidden states, and shares the target KV-cache buffers with the short `target_forward` verifier. Keep Draft KV state independent and transfer only the final Draft sliding-window hidden rows. MLX retains its existing two-method export.
Extend the bf16 Triton split-K SDPA path from single-token decode to small query blocks through Lq=4. Preserve runtime GPU `kv_len` bounds, explicit per-query masks, GQA/MQA support, and CUDA Graph safety while carrying the query-row dimension through the partial softmax accumulation and reduction. This removes the long-context verifier slowdown caused by launching too few CTAs for the fixed four-token DFlash verification block.
Add exact-output runner support and a deterministic Solo-versus-DFlash benchmark covering 512/2K/8K/32K/127K prompts, fixed 512-token greedy output, structured prefill/decode/per-call metrics, acceptance statistics, peak memory, and byte-for-byte output comparison.
Reviewed By: digantdesai
Differential Revision: D114864646
@Gasoonjia@facebook-github-bot
Add large CUDA DFlash target prefill and small-query SDPA (#21628)
612e888
Summary:
Add a CUDA-only `target_prefill` method that follows the Solo target prefill path for large prompt chunks, returns final-row logits plus tapped hidden states, and shares the target KV-cache buffers with the short `target_forward` verifier. Keep Draft KV state independent and transfer only the final Draft sliding-window hidden rows. MLX retains its existing two-method export.
Extend the bf16 Triton split-K SDPA path from single-token decode to small query blocks through Lq=4. Preserve runtime GPU `kv_len` bounds, explicit per-query masks, GQA/MQA support, and CUDA Graph safety while carrying the query-row dimension through the partial softmax accumulation and reduction. This removes the long-context verifier slowdown caused by launching too few CTAs for the fixed four-token DFlash verification block.
Add exact-output runner support and a deterministic Solo-versus-DFlash benchmark covering 512/2K/8K/32K/127K prompts, fixed 512-token greedy output, structured prefill/decode/per-call metrics, acceptance statistics, peak memory, and byte-for-byte output comparison.
Reviewed By: digantdesai
Differential Revision: D114864646
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}
} catch(__e) { console.warn('[Userscript:Universal Dark Mode]', __e); }
})();
})();

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Add large CUDA DFlash target prefill and small-query SDPA (#21628) - #21628
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Add large CUDA DFlash target prefill and small-query SDPA (#21628)#21628
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Summary:
Add a CUDA-only target_prefill method that follows the Solo target prefill path for large prompt chunks, returns final-row logits plus tapped hidden states, and shares the target KV-cache buffers with the short target_forward verifier. Keep Draft KV state independent and transfer only the final Draft sliding-window hidden rows. MLX retains its existing two-method export.
Extend the bf16 Triton split-K SDPA path from single-token decode to small query blocks through Lq=4. Preserve runtime GPU kv_len bounds, explicit per-query masks, GQA/MQA support, and CUDA Graph safety while carrying the query-row dimension through the partial softmax accumulation and reduction. This removes the long-context verifier slowdown caused by launching too few CTAs for the fixed four-token DFlash verification block.
Add exact-output runner support and a deterministic Solo-versus-DFlash benchmark covering 512/2K/8K/32K/127K prompts, fixed 512-token greedy output, structured prefill/decode/per-call metrics, acceptance statistics, peak memory, and byte-for-byte output comparison.
Reviewed By: digantdesai
Differential Revision: D114864646
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🔗 Helpful Links
🧪 See artifacts and rendered test results at hud.pytorch.org/pr/pytorch/executorch/21628
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This PR needs a release notes: label
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Add large CUDA DFlash target prefill and small-query SDPAAdd large CUDA DFlash target prefill and small-query SDPA (#21628)Aug 7, 2026
meta-codesyncBot
pushed a commit
that referenced
this pull request
Aug 7, 2026
@Gasoonjia@facebook-github-bot
Add large CUDA DFlash target prefill and small-query SDPA (#21628)
5b1ce33
Summary:
Add a CUDA-only `target_prefill` method that follows the Solo target prefill path for large prompt chunks, returns final-row logits plus tapped hidden states, and shares the target KV-cache buffers with the short `target_forward` verifier. Keep Draft KV state independent and transfer only the final Draft sliding-window hidden rows. MLX retains its existing two-method export.
Extend the bf16 Triton split-K SDPA path from single-token decode to small query blocks through Lq=4. Preserve runtime GPU `kv_len` bounds, explicit per-query masks, GQA/MQA support, and CUDA Graph safety while carrying the query-row dimension through the partial softmax accumulation and reduction. This removes the long-context verifier slowdown caused by launching too few CTAs for the fixed four-token DFlash verification block.
Add exact-output runner support and a deterministic Solo-versus-DFlash benchmark covering 512/2K/8K/32K/127K prompts, fixed 512-token greedy output, structured prefill/decode/per-call metrics, acceptance statistics, peak memory, and byte-for-byte output comparison.
Reviewed By: digantdesai
Differential Revision: D114864646
meta-codesyncBot
pushed a commit
that referenced
this pull request
Aug 7, 2026
@Gasoonjia@facebook-github-bot
Add large CUDA DFlash target prefill and small-query SDPA (#21628)
210656a
Summary:
Add a CUDA-only `target_prefill` method that follows the Solo target prefill path for large prompt chunks, returns final-row logits plus tapped hidden states, and shares the target KV-cache buffers with the short `target_forward` verifier. Keep Draft KV state independent and transfer only the final Draft sliding-window hidden rows. MLX retains its existing two-method export.
Extend the bf16 Triton split-K SDPA path from single-token decode to small query blocks through Lq=4. Preserve runtime GPU `kv_len` bounds, explicit per-query masks, GQA/MQA support, and CUDA Graph safety while carrying the query-row dimension through the partial softmax accumulation and reduction. This removes the long-context verifier slowdown caused by launching too few CTAs for the fixed four-token DFlash verification block.
Add exact-output runner support and a deterministic Solo-versus-DFlash benchmark covering 512/2K/8K/32K/127K prompts, fixed 512-token greedy output, structured prefill/decode/per-call metrics, acceptance statistics, peak memory, and byte-for-byte output comparison.
Reviewed By: digantdesai
Differential Revision: D114864646
meta-codesyncBot
pushed a commit
that referenced
this pull request
Aug 7, 2026
@Gasoonjia@facebook-github-bot
Add large CUDA DFlash target prefill and small-query SDPA (#21628)
4cba495
Summary:
Add a CUDA-only `target_prefill` method that follows the Solo target prefill path for large prompt chunks, returns final-row logits plus tapped hidden states, and shares the target KV-cache buffers with the short `target_forward` verifier. Keep Draft KV state independent and transfer only the final Draft sliding-window hidden rows. MLX retains its existing two-method export.
Extend the bf16 Triton split-K SDPA path from single-token decode to small query blocks through Lq=4. Preserve runtime GPU `kv_len` bounds, explicit per-query masks, GQA/MQA support, and CUDA Graph safety while carrying the query-row dimension through the partial softmax accumulation and reduction. This removes the long-context verifier slowdown caused by launching too few CTAs for the fixed four-token DFlash verification block.
Add exact-output runner support and a deterministic Solo-versus-DFlash benchmark covering 512/2K/8K/32K/127K prompts, fixed 512-token greedy output, structured prefill/decode/per-call metrics, acceptance statistics, peak memory, and byte-for-byte output comparison.
Reviewed By: digantdesai
Differential Revision: D114864646
meta-codesyncBot
pushed a commit
that referenced
this pull request
Aug 7, 2026
@Gasoonjia@facebook-github-bot
Add large CUDA DFlash target prefill and small-query SDPA (#21628)
c3f2b7b
Summary:
Add a CUDA-only `target_prefill` method that follows the Solo target prefill path for large prompt chunks, returns final-row logits plus tapped hidden states, and shares the target KV-cache buffers with the short `target_forward` verifier. Keep Draft KV state independent and transfer only the final Draft sliding-window hidden rows. MLX retains its existing two-method export.
Extend the bf16 Triton split-K SDPA path from single-token decode to small query blocks through Lq=4. Preserve runtime GPU `kv_len` bounds, explicit per-query masks, GQA/MQA support, and CUDA Graph safety while carrying the query-row dimension through the partial softmax accumulation and reduction. This removes the long-context verifier slowdown caused by launching too few CTAs for the fixed four-token DFlash verification block.
Add exact-output runner support and a deterministic Solo-versus-DFlash benchmark covering 512/2K/8K/32K/127K prompts, fixed 512-token greedy output, structured prefill/decode/per-call metrics, acceptance statistics, peak memory, and byte-for-byte output comparison.
Reviewed By: digantdesai
Differential Revision: D114864646
meta-codesyncBot
pushed a commit
that referenced
this pull request
Aug 7, 2026
@Gasoonjia@facebook-github-bot
Add large CUDA DFlash target prefill and small-query SDPA (#21628)
817e5c2
Summary:
Add a CUDA-only `target_prefill` method that follows the Solo target prefill path for large prompt chunks, returns final-row logits plus tapped hidden states, and shares the target KV-cache buffers with the short `target_forward` verifier. Keep Draft KV state independent and transfer only the final Draft sliding-window hidden rows. MLX retains its existing two-method export.
Extend the bf16 Triton split-K SDPA path from single-token decode to small query blocks through Lq=4. Preserve runtime GPU `kv_len` bounds, explicit per-query masks, GQA/MQA support, and CUDA Graph safety while carrying the query-row dimension through the partial softmax accumulation and reduction. This removes the long-context verifier slowdown caused by launching too few CTAs for the fixed four-token DFlash verification block.
Add exact-output runner support and a deterministic Solo-versus-DFlash benchmark covering 512/2K/8K/32K/127K prompts, fixed 512-token greedy output, structured prefill/decode/per-call metrics, acceptance statistics, peak memory, and byte-for-byte output comparison.
Reviewed By: digantdesai
Differential Revision: D114864646
@Gasoonjia@facebook-github-bot
Add large CUDA DFlash target prefill and small-query SDPA (#21628)
612e888
Summary:
Add a CUDA-only `target_prefill` method that follows the Solo target prefill path for large prompt chunks, returns final-row logits plus tapped hidden states, and shares the target KV-cache buffers with the short `target_forward` verifier. Keep Draft KV state independent and transfer only the final Draft sliding-window hidden rows. MLX retains its existing two-method export.
Extend the bf16 Triton split-K SDPA path from single-token decode to small query blocks through Lq=4. Preserve runtime GPU `kv_len` bounds, explicit per-query masks, GQA/MQA support, and CUDA Graph safety while carrying the query-row dimension through the partial softmax accumulation and reduction. This removes the long-context verifier slowdown caused by launching too few CTAs for the fixed four-token DFlash verification block.
Add exact-output runner support and a deterministic Solo-versus-DFlash benchmark covering 512/2K/8K/32K/127K prompts, fixed 512-token greedy output, structured prefill/decode/per-call metrics, acceptance statistics, peak memory, and byte-for-byte output comparison.
Reviewed By: digantdesai
Differential Revision: D114864646
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merged commit 82fcf09
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199 of 201 checks passed

@meta-codesync
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@shoumikhinshoumikhin
mentioned this pull request
Aug 25, 2026
 Merged

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