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docs: add AutoQuantize mixed-precision search blog - #1979

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@realAsma realAsma commented Jul 15, 2026

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What does this PR do?

Type of change: documentation.

Adds the AutoQuantize technical blog to the announcements system introduced by #1971.

  • Preserves the source derivation, deployment-aware search details, results, usage example, and references in native Sphinx RST.
  • Adds the MMLU accuracy-versus-effective-bits figure as a losslessly optimized asset.
  • Adds a newest-first landing-page card and AutoQuantize filter.
  • Credits the authors in this order: Asma Beevi K T, Wei Ming, Frida Hou, Juhi Mittal, Jenny Chen, Ajinkya Rasane, Meng Xin.

This is a stacked PR targeting the branch for #1971. After #1971 merges, this PR can be retargeted to main.

Usage

N/A; documentation only.

Testing

  • Focused pre-commit hooks on all three changed files.
  • git diff --check.
  • Focused Sphinx HTML build for the announcement and landing page.
  • Rendered-output checks for equations, table, Python code block, image and alt text, references, external links, card, filter, and exact author order.
  • Full fail-on-warning build was attempted; remaining warnings were unrelated optional autodoc environment warnings.

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  • Is this change backward compatible?: ✅
  • If you copied code from any other sources or added a new PIP dependency, did you follow guidance in CONTRIBUTING.md: N/A
  • Did you write any new necessary tests?: N/A
  • Did you update Changelog?: N/A
  • Did you get Claude approval on this PR?: N/A

Additional Information

Depends on #1971.

Summary by CodeRabbit

  • Documentation
    • Added a comprehensive announcement introducing AutoQuantize for gradient-based mixed-precision optimization.
    • Documented sensitivity scoring, effective-bits cost modeling, deployment-aware grouping, benchmark results, usage examples, future plans, and references.
    • Added the announcement to the documentation homepage with an August 24, 2026 release card from the Model Optimizer Team.

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📝 Walkthrough

Walkthrough

Added a comprehensive AutoQuantize announcement. Registered it on the documentation index with a filter button and an announcement card dated August 24, 2026.

Changes

AutoQuantize documentation

Layer / File(s) Summary
Announcement content and homepage entry
docs/source/announcements/autoquantize.rst, docs/source/index.rst
Added AutoQuantize technical details, evaluation results, usage examples, future work, references, and documentation index navigation.

Estimated code review effort: 1 (Trivial) | ~5 minutes

Merge Risk: ⚪ Minimal · up to 14226

This documentation-only change adds the AutoQuantize article, figure, landing-page card, and filter without introducing an actionable merge-blocking risk; it is merge-ready after normal checks and review.

Suggested reviewers: aanoosheh

🚥 Pre-merge checks | ✅ 6
✅ Passed checks (6 passed)
Check name Status Explanation
Description Check ✅ Passed Check skipped - CodeRabbit’s high-level summary is enabled.
Title check ✅ Passed The title clearly describes the main change: adding an AutoQuantize mixed-precision search blog. It is concise and directly related to the documentation changes.
Docstring Coverage ✅ Passed No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check. Docstring coverage is scoped to functions touched by this diff. Analyzed 0 functions across 0…
Linked Issues check ✅ Passed Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check ✅ Passed Check skipped because no linked issues were found for this pull request.
Security Anti-Patterns ✅ Passed PASS. The aggregate diff from the PR base contains only docs/source/announcements/autoquantize.rst, docs/source/index.rst, and one PNG asset. It contains no changes under modelopt or examples,…
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PASS. The aggregate diff from the PR base contains only docs/source/announcements/autoquantize.rst, docs/source/index.rst, and one PNG asset. It contains no changes under modelopt or examples, no Python files, and no pyproject.toml or requirements files. The changed text has no weights_only=False, allow_pickle=True, hardcoded trust_remote_code=True, eval(, exec(, or # nosec pattern.

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Comment thread docs/source/announcements/autoquantize.rst Outdated
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A mixed-precision assignment is only useful if the runtime can execute it. So AutoQuantize performs a deployment-aware search — runtime coupling constraints are folded into the search rather than patched up afterwards, meaning the searched model is deployable out of the box in vLLM, SGLang, TensorRT-LLM, and similar inference runtimes. Any restriction of the form "this group of operators takes one joint format decision" becomes a merged knapsack item with aggregated sensitivity and cost.

**1) Joint quantization for fused linear layers.** Inference runtimes often fuse linear operators, which imposes a shared quantization format across the fused group. This constraint is applied within each layer: that layer's Q, K, and V projections are fused and must share one format, so the fused QKV projection becomes a single decision variable. The naive score would just sum the three per-projection sensitivities — but that treats their Hessians as independent, when the three outputs actually interact through the attention operation. Instead, AutoQuantize quantizes all three projections jointly with format :math:`f` and measures the sensitivity at the attention output, so the metric naturally captures how the projections' quantization errors combine through attention:

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Looks like there's no score rule to redirect QKV to an attention output, we only have that for MoEs: https://github.com/NVIDIA/Model-Optimizer/blob/main/modelopt/torch/quantization/algorithms.py#L1027

In my understanding the QKV will actually get a summed score

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Yes, @meenchen had recently implemented that and found that it was better. So I am keeping that here instead of making it confusing.

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I see, is it this PR:#1878? We should consider merging it if it works better :)

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@Fridah-nv agreed! I need to dig up the PR. I am removing this QKV specifics from the blog since I found it did not show much improvements. see https://docs.google.com/presentation/d/1Mxu8YpvhzSP70Ca4jomLh23FOZ_vkRUVhSW6w5wHJ5g/edit?slide=id.g3f7967c23e8_0_0#slide=id.g3f7967c23e8_0_0

@meenchen once you get a chance, could please create the PR for QKV scoring at the self attention output and update this blog if you find enough evidence for QKV scoring at self attention output is better than summing QKV scores?

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High-priority documentation correctness findings are inline.

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/claude review

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Claude review passed — no blocking issues found. LGTM

Scope: Documentation-only PR (3 files: new docs/source/announcements/autoquantize.rst, one PNG asset, and a landing-page card/filter in docs/source/index.rst). Reviewed the RST blog and index changes; the binary PNG was not opened.

What I verified:

  • The mtq.auto_quantize(...) code example matches the real public API: signature/argument names (constraints, quantization_formats, data_loader, forward_step, loss_func, num_calib_steps, num_score_steps), the model, search_state = ... return-value unpacking, and the NVFP4_DEFAULT_CFG/FP8_DEFAULT_CFG config constants all exist in modelopt/torch/quantization.
  • The sensitivity-score derivation (Taylor → OBS → diagonal-Fisher/squared-gradient approximation) is internally consistent and correctly presented.
  • The landing-page card in index.rst is consistent with the RST (title, date, tags, author order all match); newest-first ordering is preserved.

Findings (1 SUGGESTION, non-blocking):

  • The benchmark model name Qwen3.6-35B-A3B (Table 1 timing paragraph) does not correspond to a real Qwen3 release — the MoE model with 3B active params is Qwen3-30B-A3B. Since this is customer-facing published content, please confirm the exact model used and correct the identifier before publishing. (Inline comment posted.)

Risk: Low — docs-only, no code/API/state changes.

Comment thread docs/source/announcements/assets/autoquantize-qwen3-mmlu-effective-bits.png Outdated
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ChenhanYu force-pushed the chenhany/omniml-5476 branch from b3adca8 to 485356b Compare August 13, 2026 17:15
Base automatically changed from chenhany/omniml-5476 to main August 13, 2026 21:04
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realAsma force-pushed the asma/autoquantize-blog branch from 99d5321 to 5749db2 Compare August 20, 2026 21:43
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Preview removed because the pull request was closed.
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Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 78.61%. Comparing base (73d7784) to head (1422658).
⚠️ Report is 4 commits behind head on main.

Additional details and impacted files
@@            Coverage Diff             @@
##             main    #1979      +/-   ##
==========================================
- Coverage   79.01%   78.61%   -0.41%     
==========================================
  Files         523      523              
  Lines       60695    61029     +334     
==========================================
+ Hits        47960    47978      +18     
- Misses      12735    13051     +316     
Flag Coverage Δ
unit 55.62% <ø> (-0.05%) ⬇️

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/claude review

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Claude review — 2 IMPORTANT, 4 SUGGESTION

Scope: Full review of all 3 changed files (docs-only, +187/-0): the new docs/source/announcements/autoquantize.rst, the landing-page card/filter in docs/source/index.rst, and the PNG asset (binary, not opened).

Because this is a technical blog describing a shipped algorithm, I traced every behavioral claim against the implementation in modelopt/torch/quantization/ rather than reviewing prose in isolation.

Findings by severity — CRITICAL: 0 · IMPORTANT: 2 · SUGGESTION: 4

IMPORTANT — both in the MoE layer constraints section

  1. gate_proj is missing from the grouped sparse-expert projections (line 90). The rule at algorithms.py:642-643 groups gate_proj|up_proj|down_proj for Qwen3-like MoE; only the NemotronH .mixer.experts variant is up_proj+down_proj. The blog documents the NemotronH shape, while the results figure and Table 1 timing are both on Qwen3 models — so the one case a reader will map onto their own model is the case the sentence gets wrong.

  2. 'so each is searched independently' over-claims for shared experts (line 96). Shared experts do escape the all-experts restriction, but their gate_proj/up_proj remain coupled by the generic gate/up fusion rule at algorithms.py:647. Only down_proj and the latent projections are truly independent. This section is specifically about which decisions are coupled, so the imprecision lands on the exact property being documented.

Both are small wording fixes, but this is customer-facing published content about coupling constraints, so they are worth getting right before it goes live.

SUGGESTION

  1. The 'fused linear layers' section covers only QKV, though quant_grouping_rules also couples gate/up, Mixtral w1/w2/w3, MCore linear_fc1/fc2, and the Qwen3.5/3.6 in_proj_qkvz/in_proj_ba pairs.
  2. Lines 15 and 158 use the pre-rename NVIDIA/TensorRT-Model-Optimizer URL; all 31 other GitHub self-references under docs/source/ use NVIDIA/Model-Optimizer. Redirects work, so cosmetic.
  3. ~51x vs Table 1's ~14 h / ~16 min = ~52.5x.
  4. index.rst card omits modelopt from its visible tag spans; both existing cards render all their data-tags.

Retracting a prior false positive

An earlier Claude review on this PR flagged Qwen3.6-35B-A3B as not a real model. That was wrong — please disregard it. The model appears in this repo's own support matrix (docs/source/deployment/3_unified_hf.rst:125, 'Qwen 3.6 35B-A3B / NVFP4') and has a dedicated recipe tree at modelopt_recipes/huggingface/qwen3_6_moe/. No change needed there.

What I verified as correct

  • API example matches the real signature (model_quant.py:272-288): argument names, the (model, state_dict) tuple return, and num_calib_steps=512/num_score_steps=128 are even the actual library defaults. NVFP4_DEFAULT_CFG/FP8_DEFAULT_CFG and the constraints={'effective_bits': ...} key all check out.
  • The score formula matches the code exactly. The blog's sum of g^2 * (Y - Y_Q)^2 over the feature dim is precisely _get_auto_quantize_score (algorithms.py:1432-1434): (grad.float() * output_diff.float()).square().sum(), including the fp32 upcast. The Taylor expansion signs are right (the -g^T (Y - Y_Q) convention is consistent with delta = Y_Q - Y), and the proportionality correctly absorbs the dropped 1/2.
  • The complexity claims and the headline speedup framing hold. The KL path (algorithms.py:1836-1858) really does a full forward_step per (hparam, recipe) inside the batch loop, giving O(N_layers^2 * N_formats); the gradient path replays candidates locally in a forward hook plus one backward per batch, giving O(N_layers) * O(N_formats).
  • QKV claims are accurate: algorithms.py:639 groups the three projections, and the absence of a q/k/v score_module_rule confirms sensitivity is measured at each projection's own output. The MoE-block-output scoring claim matches score_module_rules at algorithms.py:1476-1477.
  • Effective-bits cost model matches the documented precedence (explicit effective_bits, else num_bits) at algorithms.py:209-249, and the knapsack constraint matches total_cost / total_weight_size * 16.
  • Docs plumbing: :orphan: matches both sibling announcements, card ordering is correctly newest-first (08-13, 07-15, 07-13), the filter button's data-tag matches the card's data-tags, and the examples/hf_ptq#autoquantize anchor resolves to a real ## AutoQuantize heading.

Risk: Low. Docs-only — no code, public API, mode registration, modelopt_state, or export path is touched, and codecov confirms zero coverable lines changed. The two IMPORTANT items are accuracy-of-published-content issues, not runtime risk. Once the two MoE sentences are corrected, this is good to publish.

Signed-off-by: realAsma <akuriparambi@nvidia.com>
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realAsma force-pushed the asma/autoquantize-blog branch from 5749db2 to cfbc1c7 Compare August 24, 2026 21:21
Signed-off-by: realAsma <akuriparambi@nvidia.com>
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/claude review

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Claude review — 2 IMPORTANT, 2 SUGGESTION

Scope: Full review of all 3 changed files (docs-only, +186/-0): the new docs/source/announcements/autoquantize.rst, the landing-page card/filter in docs/source/index.rst, and the PNG asset (binary, not opened). As in the prior round, I traced behavioral claims against modelopt/torch/quantization/ rather than reviewing prose in isolation, and re-checked the landing-page plumbing (_static/announcements.js) since the card changed.

Findings by severity — CRITICAL: 0 · IMPORTANT: 2 · SUGGESTION: 2

IMPORTANT — both are card-vs-article inconsistencies in index.rst, and both look introduced by the latest commit rather than deliberate

  1. Date mismatch, which also mis-sorts the card. The article says :Date: August 24, 2026 (autoquantize.rst:7); the card says data-date="2026-07-15" / July 15, 2026. _static/announcements.js:3-5 re-sorts cards by data-date descending, so this post renders third — below the 2026-08-13 release card — while the article claims to be the newest. Pick the intended date, sync all three spots (RST :Date:, data-date, visible meta), and if Aug 24 is right, move the <article> block above the 2026-08-13 card so source order matches rendered order.

  2. The article lost its named author credits. The card credits eight people; autoquantize.rst:6 now reads :Author: Model Optimizer Team. The PR description explicitly says the blog credits the named authors, and a prior review round verified the two matched — so the named list was there and has since been replaced. Both sibling announcements keep card meta and RST :Author: identical, so this is the only card that disagrees with its article. Worth fixing carefully since it is real-contributor credit on published content. (Note: Shengliang Xu is on the card but not in the PR description's list — worth confirming the intended set and order.)

SUGGESTION

  1. Line 81 is in the wrong place. The new "same grouping mechanism covers other supported fused layouts" sentence was inserted between line 79's colon-terminated lead-in and the QKV formula on line 85, so the page renders a dangling colon, an unrelated paragraph, then an orphaned equation — and line 87's explanation refers back to that formula. The sentence's content is accurate against quant_grouping_rules; only its position is wrong. Suggested placement is inline.

  2. "the Qwen3 models benchmarked here" (line 89) is loose. Figure 1 sweeps Qwen3.5-2B/9B (dense — the repo separates modelopt_recipes/huggingface/qwen3_5/ from qwen3_5_moe/), while only Table 1's Qwen3.6-35B-A3B is MoE. Naming that model directly avoids pointing MoE-grouping behavior at models it cannot apply to.

Prior-round findings — all six are resolved

  • gate_proj now included in the grouped sparse-expert projections (line 89) ✅
  • shared-expert coupling now stated precisely: gate/up share a format, down_proj searched separately (line 95) — matches the generic gate/up rule with no down_proj rule ✅
  • fused-layout coverage generalized beyond QKV (line 81, modulo the placement issue above) ✅
  • pre-rename TensorRT-Model-Optimizer URLs now NVIDIA/Model-Optimizer
  • ~51x~52×, consistent with Table 1's ~14 h / ~16 min ✅
  • card now renders all four data-tags as visible spans ✅

Re-verified as correct this round

  • quant_grouping_rules (algorithms.py:638-655) backs the QKV, MoE-expert, and shared-expert claims exactly as written, including the .mlp.experts.<N>. gate/up/down group key.
  • The mtq.auto_quantize(...) example still matches the public signature — argument names, the (model, search_state) tuple return, NVFP4_DEFAULT_CFG/FP8_DEFAULT_CFG, and the constraints / effective_bits key.
  • Score formula, Taylor/diagonal-Fisher derivation, complexity claims, and the effective-bits cost model are unchanged from the prior round and still check out.
  • Model identifiers are real: Qwen3.6-35B-A3B and the Qwen3.5 families both appear in this repo's recipes and support matrix. (An early review on this PR wrongly flagged Qwen3.6-35B-A3B; that was already retracted — no action needed.)
  • Docs plumbing: :orphan: matches both siblings, the filter button's data-tag="autoquantize" matches the card's data-tags, and the hf_ptq#autoquantize anchor resolves.

Risk: Low. Docs-only — no code, public API, mode registration, modelopt_state, or export path touched; codecov confirms zero coverable lines changed. Both IMPORTANT items are metadata consistency issues in customer-facing published content, not runtime risk, and all four findings are small edits. Once the date and author fields agree between the card and the article, this is good to publish.

Signed-off-by: realAsma <akuriparambi@nvidia.com>
Signed-off-by: realAsma <akuriparambi@nvidia.com>
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realAsma marked this pull request as ready for review August 24, 2026 22:28
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realAsma requested a review from a team as a code owner August 24, 2026 22:28

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Inline comments:
In `@docs/source/announcements/autoquantize.rst`:
- Line 106: Update the AutoQuantize gradient-scoring complexity description in
the paragraph contrasting direct sensitivity measurement so it accounts for
replaying every candidate format at each scored module, plus the single backward
pass. Replace the current O(N_layers) claim with complexity consistent with
Table 1: O(N_layers) × O(N_formats), while preserving the surrounding comparison
and speedup statement.

In `@docs/source/index.rst`:
- Around line 33-34: Align the announcement-card date and displayed date in the
landing page with the canonical date declared by the AutoQuantize announcement,
then reorder the card chronologically relative to the August 13, 2026 entry if
needed. Update only the AutoQuantize card in the landing-page announcements
markup and preserve its existing metadata.
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The content LGTM, left minor comments, thanks!

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Thanks @realAsma , looks really good and comprehensive!

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LGTM

Comment thread docs/source/announcements/autoquantize.rst
Signed-off-by: realAsma <akuriparambi@nvidia.com>
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realAsma enabled auto-merge (squash) August 26, 2026 21:43
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realAsma merged commit 8c04ce6 into main Aug 26, 2026
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realAsma deleted the asma/autoquantize-blog branch August 26, 2026 21:49
AutoQuantize gradient is fast!
==============================

Direct sensitivity measurement evaluates the full model for every layer-format pair. For instance, KL-divergence-based mixed-precision assignment algorithms, including AutoQuantize KL-divergence scoring, quantize one layer at a time and compare the output distributions of the quantized and unquantized models. Because each layer requires a full-model pass, scoring scales as :math:`O(N_{\mathrm{layers}}^2)`. In contrast, for each scoring batch, AutoQuantize gradient scoring uses one backward pass and locally replays every candidate format at each scored module. Hence, its scoring work scales as :math:`O(N_{\mathrm{layers}} \times N_{\mathrm{formats}})`, resulting in a ~52× speedup on Qwen3.6-35B-A3B (Table 1).

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[SUGGESTION] The prose complexity for KL-divergence scoring contradicts Table 1 four lines below.

This sentence says scoring scales as :math:O(N_{\mathrm{layers}}^2), but Table 1 lists KL divergence as :math:O(N_{\mathrm{layers}}^2 \times N_{\mathrm{formats}}). The table is the correct one: the paragraph opens with "evaluates the full model for every layer-format pair", so there are :math:N_{\mathrm{layers}} \times N_{\mathrm{formats}} full-model passes, each costing :math:O(N_{\mathrm{layers}}).

Why it matters: the whole point of this section is the gradient-vs-KL asymptotic contrast. Dropping :math:N_{\mathrm{formats}} from the KL side understates the gap and makes the two numbers in the same section disagree, which a reader will notice immediately.

Fix — carry the format factor through in the prose so it matches the table:

Because each layer-format pair requires a full-model pass, scoring scales as
:math:`O(N_{\mathrm{layers}}^2 \times N_{\mathrm{formats}})`.


*ModelOpt AutoQuantize supports both sensitivity scoring methods — gradient (the default) and KL divergence. Measured on 4× NVIDIA RTX 6000 Ada GPUs with 128 samples at sequence length 512. Times cover sensitivity scoring only — not the end-to-end AutoQuantize run, which also includes calibration time for each format.*

**Memory.** By default, AutoQuantize uses activation recomputation for gradient scoring. This is memory efficient because it avoids retaining all intermediate tensors from the forward pass. As shown in Table 1, the resulting peak memory overhead over a forward-only pass is small.

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[SUGGESTION] "By default" overstates where activation recomputation actually kicks in.

In AutoQuantizeGradientSearcher.estimate_sensitivity_scores (modelopt/torch/quantization/algorithms.py:1681-1690), the gradient-checkpointing context is only used when a registered _custom_support predicate matches the model; otherwise it falls back to nullcontext():

grad_checkpointing_ctxt = None
for is_supported_checker, ctxt_candidate, grad_enabled_candidate in self._custom_support:
    if is_supported_checker(self.model):
        grad_checkpointing_ctxt = ctxt_candidate
        ...
with grad_checkpointing_ctxt(self.model) if grad_checkpointing_ctxt else nullcontext():

register_custom_support is called in exactly two places — plugins/huggingface.py:1861 and plugins/megatron.py:986. So recomputation applies to HF and Megatron-Core models, not to arbitrary nn.Module models.

Why it matters: this paragraph is the blog's only statement about AutoQuantize's memory profile, and Table 1's 29 GB number is what readers will budget against. Someone running AutoQuantize on a custom (non-HF, non-MCore) model gets full activation retention and a substantially different peak, with nothing in the blog to explain why.

Fix — qualify the scope in one clause:

**Memory.** For Hugging Face and Megatron-Core models, AutoQuantize enables activation
recomputation for gradient scoring by default. This is memory efficient because it avoids
retaining all intermediate tensors from the forward pass.


AutoQuantize turns mixed-precision quantization from trial and error into a principled search: gradient-based sensitivity scoring in a single sweep, optimization with an ILP solver under your cost budget, and selected runtime coupling constraints incorporated into the assignment. Sweep the bit budget to find your model's accuracy-vs-compression sweet spot, then follow the documented export and deployment workflow for the target model, formats, and runtime.

.. _references:

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[SUGGESTION] Use a namespaced label instead of the generic references.

Sphinx _labels live in a single global namespace across the whole doc set. references is the most likely name any future announcement will reach for, and the second one to use it produces a duplicate label warning — which matters here because the announcements landing page is meant to accumulate pages over time, and this repo builds docs fail-on-warning.

The sibling announcement already follows the namespaced convention: dspark-vs-domino.rst defines dspark-domino-references and cross-references it as :ref:`dspark-domino-references` . This label is also currently unreferenced from anywhere in the file, so renaming it costs nothing.

Suggested change
.. _references:
.. _autoquantize-references:

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Claude review passed — no blocking issues found. LGTM

Scope. Full review (trigger had no scoping instructions). 3 files changed, +180/-0 — all reviewed: docs/source/announcements/autoquantize.rst (new, 173 lines), docs/source/index.rst (+7), and the new PNG asset (binary, not opened). Since this PR's entire value is the accuracy of its technical claims, I spent the budget verifying the blog against the actual AutoQuantize implementation rather than on prose review — CodeRabbit already covers style/typos and reported no actionable comments.

Findings — CRITICAL: 0 · IMPORTANT: 0 · SUGGESTION: 3

  1. Line 106 — KL-divergence complexity in the prose (O(N_layers^2)) contradicts Table 1 four lines below (O(N_layers^2 x N_formats)). The table is right; the prose drops the format factor it just introduced, understating the gradient-vs-KL gap that is the whole point of the section.
  2. Line 128 — 'By default, AutoQuantize uses activation recomputation' is narrower in the code: register_custom_support is called only from the HF and Megatron-Core plugins, and everything else falls back to nullcontext(). Worth qualifying, since Table 1's 29 GB is the number readers will budget against.
  3. Line 165 — generic .. _references: label sits in Sphinx's global namespace; dspark-vs-domino.rst already uses the namespaced dspark-domino-references. Collision risk as announcements accumulate, and the label is currently unreferenced so renaming is free.

Technical claims verified against modelopt/. Everything substantive checked out — this is unusually well-grounded for a blog post:

  • Sensitivity score S ∝ Σ g² (Y − Y^Q)² matches _get_auto_quantize_score (algorithms.py:1432, (grad * diff).square().sum()). Taylor-expansion signs in the first equation are also correct.
  • ILP claim ('one binary variable for every candidate format in each search decision… selects exactly one format per decision') matches searcher.py:344-370pulp.LpBinary vars with one-hot plus budget constraints. Genuinely an ILP, not an LP relaxation.
  • Effective-bits constraint Σ N_params × bits ≤ N_total × b̄ is exactly the code's total_cost ≤ total_weight_size × (effective_bits/16).
  • NVFP4 = 4.5 is correct and not merely the paper value: modelopt_recipes/configs/numerics/nvfp4.yaml sets effective_bits: 4.5 explicitly, and its comment confirms the num_bits heuristic would under-count it as 4.0. The blog's 'format-provided overhead when an explicit effective-bits value is available; otherwise… num_bits' precisely describes estimate_quant_compression.
  • 'Embeddings, norms, and other parameters outside the search are not included' matches _get_total_weight_size, which sums only _is_auto_quantize_module weights.
  • Grouping claims match quant_grouping_rules (algorithms.py:640-657): QKV grouped, gate+up grouped for dense MLP with down_proj separate, all routed MoE experts collapsed into one decision, shared experts left as their own decision.
  • 'Sensitivity measured jointly at the MoE block output' matches AutoQuantizeGradientSearcher.score_module_rules (algorithms.py:1475-1479), which redirects expert projections to the .mlp output.
  • API snippet matches auto_quantize's signature and its documented (model, state_dict) return; quantization_formats accepts config dicts, so mtq.NVFP4_DEFAULT_CFG is valid.
  • ~52x speedup is consistent with Table 1 (14 h / 16 min ≈ 52.5x).
  • Landing-page wiring: the new card's data-tags includes autoquantize and announcements.js filters via exact split(' ').includes(activeTag), so the new button resolves correctly. :orphan: plus raw-HTML card linking matches both existing announcements; card date and page date agree (2026-08-24).

Note on the PR description. It says the change 'credits the authors in this order: Asma Beevi K T, Wei Ming, Frida Hou, Juhi Mittal, Jenny Chen, Ajinkya Rasane, Meng Xin,' but the committed file and the landing-page card both attribute to Model Optimizer Team. If that was the deliberate outcome of the earlier review feedback, the description is just stale — worth reconciling so the final PR record isn't misleading.

Risk: low. Documentation-only; no library code, mode/state, config schema, or export surface touched. All three findings are non-blocking precision improvements.

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6 participants