REVIEW 5 major objections 6 minor 23 references
Pruning-style scores can fix a tiny set of weights to train, and the lowest-scoring ones often make the best sparse adapters.
Reviewed by Pith at T0; open to challenge. T0 means a machine referee read the full paper against a public rubric. the ladder, T0–T4 →
T0 review · grok-4.5
2026-07-13 04:07 UTC pith:UHA5VG46
load-bearing objection Useful PEFT engineering with honest hedges: Wanda/magnitude fixed supports can work, but the headline ranking is best-of-grid, not fixed-protocol superiority. the 5 major comments →
Super-Tuning: From Activation-Aware Pruning to Sparse Fine-Tuning
The pith
A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.
Core claim
Under matched rank-equivalent trainable-parameter budgets, fixed sparse supports chosen once by a training-free Wanda-style or magnitude score—especially BottomK low-score supports—yield competitive or best-in-comparison average arithmetic accuracy for PEFT, and combining those supports with LoRA under an explicit budget split (Supra) can preserve or improve that result without extra trainable parameters.
What carries the argument
The Wanda-style score A_ij = |W_ij| · ||X_j:||_2 (or magnitude-only |W_ij|), computed from a calibration pass, ranks layer weights so Super/Supra can lock a fixed TopK or BottomK sparse mask; Supra then converts a target parameter budget into a LoRA rank and residual sparse count via a simple floor rule on the low-rank budget fraction λ.
Load-bearing premise
That single-seed, validation-picked learning rates and best-of-one-or-three-epoch summaries on arithmetic-only benchmarks fairly show these fixed low-score supports remain useful when the task or model scale changes.
What would settle it
Multi-seed Math17K (or non-math) runs in which, under the same matched budget and validation LR protocol, BottomK Super/Supra and magnitude masks consistently fall below LoRA and random sparse supports on average exact-answer accuracy.
If this is right
- Practitioners can build sparse PEFT masks with one calibration pass and no gradients, then train only those entries.
- Low-score (BottomK) pretrained coordinates are a strong default support to try before TopK or random masks.
- Splitting a fixed parameter budget between sparse updates and LoRA can match or beat pure LoRA without raising the trainable count.
- Magnitude-only ranking is a viable no-calibration alternative when activation statistics are unavailable.
- Pruning metrics can be repurposed as adaptation-site selectors rather than only as deletion criteria.
Where Pith is reading between the lines
- If low-score weights are freer to move without wrecking pretrained behavior, other PEFT methods might deliberately protect high-score coordinates and concentrate learning on the low-score tail.
- Dynamic reallocation of the sparse mask during training is a natural next test: fixed BottomK may be a strong start but not the last word when tasks drift mid-training.
- The same ordering idea could be tried on structured supports (rows, heads, channels) to get real kernel speedups beyond the paper’s dense-matmul sparse implementation.
Editorial analysis
A structured set of objections, weighed in public.
Referee Report
Summary. The paper proposes Super, a sparse PEFT method that freezes a small trainable support chosen once by a Wanda-style activation-weighted magnitude score from a calibration pass, and Supra, a hybrid that splits a matched scalar-parameter budget between that fixed sparse support and LoRA via a transparent rank-conversion rule. On Math17K arithmetic fine-tuning of Llama-3.2-1B and Meta-Llama-3-8B under a rank-equivalent r0=8 budget, the authors report that the best schedule-selected Super/Supra (and Supra-Mag) variants attain the highest average exact-answer accuracy among the tested adapters. They also include PaFi-style magnitude-only supports, TopK/BottomK and hybrid-mask ablations, full one-/three-epoch grids, and implementation-level efficiency profiling, and carefully hedge the main claim as single-seed and schedule-selected.
Significance. If the finding holds under fixed protocols and broader evaluation, the work would be a useful practical contribution: it shows that training-free pruning-inspired orderings—especially low-score BottomK supports—can define competitive fixed sparse PEFT masks, alone or with LoRA, without gradient-based mask search. Strengths include explicit budget matching, a closest training-free magnitude baseline, reconstruction-identity motivation (Prop. 3.1), released code, and an honest Limitations section. The hybrid budget-splitting rule is transparent rather than adaptive. Significance is currently limited by arithmetic-only evaluation, single-seed results, and schedule/variant selection that inflate the headline ranking relative to fixed-schedule tables.
major comments (5)
- Tables 1–2 and §4.3 present schedule-selected summaries that, for each method family, take the better of one- vs three-epoch runs by average test accuracy and, for Super/Supra, the best support direction and λ from the appendix grids. This is load-bearing for the central superiority claim, yet it is not a fixed-protocol ranking: methods with more searchable configurations (λ grid, TopK/BottomK, Mag vs Wanda) are rewarded under single-seed noise. The paper’s own Limitations admit these are best-observed summaries. Primary claims and main tables should report a pre-specified protocol (fixed epoch budget, fixed default BottomK, fixed λ or a small pre-declared set) with appendix grids as secondary exploration.
- Fixed-schedule appendix tables undermine a universal Super/Supra advantage. On Llama-3.2-1B Math17K one-epoch (Table 11), Magnitude(BottomK) 59.31 and Supra-Mag(λ=0.3) 59.18 beat Super(BottomK) 37.00 and several Supra rows; on Meta-Llama-3-8B three-epoch (Table 19), Super(BottomK) 72.73 is strong but many Supra/Supra-Mag rows collapse (e.g. Supra-Mag λ=0.3 → 32.30). The abstract and §5 should be rewritten so the headline claim matches fixed-protocol evidence rather than post-hoc best-of-grid averages.
- The distinctive Super ingredient is the Wanda activation term Aij=|Wij|∥Xj:∥2 versus PaFi-style |Wij|. On the 8B schedule-selected comparison (Tables 2–3), Supra-Mag(BottomK, λ=0.3) 79.12 edges Magnitude(BottomK) 79.02 and beats Wanda-selected Supra 78.66; sparse-only Super often underperforms magnitude. §5 should state clearly that low-score pretrained-magnitude supports, not activation weighting per se, drive most of the positive sparse results, and either strengthen the case for Wanda (e.g., tasks/settings where calibration activations matter) or reframe Super as one instance of low-score fixed-support PEFT.
- All main results use a single seed (seed 0), while the 1B Supra vs LoRA gap is only 1.16 points (62.23 vs 61.07) and several 8B sparse/hybrid gaps are similarly small. §6 acknowledges this, but the abstract and §4.3 still read as method rankings. Either multi-seed means±std for the main matched-budget rows, or the claims must be demoted to single-run observations without ranking language. Small single-seed gaps under validation-selected LRs are not sufficient to establish superiority.
- Evaluation is confined to Math17K arithmetic fine-tuning and six arithmetic benchmarks on two Llama sizes (§4.1, §6). That is a narrow slice for a general PEFT method claim. At minimum, one non-arithmetic suite (e.g., commonsense or instruction-following) under the same matched budget would test whether BottomK fixed supports transfer beyond symbolic math; without it, the contribution should be scoped as arithmetic PEFT evidence rather than a general sparse-adapter recipe.
minor comments (6)
- Table 3 lists Supra(BottomK, λ=0.3) Acc. 55.03 on 1B while Table 1’s selected Supra row is λ=0.8 at 62.23; the dual λ rows are easy to misread as both being schedule-selected winners. Clarify which rows are compact winners vs diagnostic.
- Eq. (1) uses the squared Wanda score Skq=(|Wkq|∥Xq:∥2)2 while mask selection uses Aij=|Wij|∥Xj:∥2; the text notes monotonicity, but a single consistent score definition in §3.2 would reduce confusion.
- Figure 1 is schematic and helpful; adding the explicit budget split (ri=⌊λr0⌋, si=(r0−⌊λr0⌋)(ci+bi) from Eq. 22) on the figure would make Supra’s matching rule self-contained.
- Related work cites RoSA, PaFi, SIFT, and recent salience-aware sparse PEFT; a short explicit contrast table (score, static vs dynamic mask, hybrid with LoRA, training-free?) would sharpen novelty relative to RoSA and PaFi.
- Efficiency Table 5 notes dense matmul/grad gather for sparse layers; the abstract’s efficiency narrative should not imply sparse-kernel speedups beyond measured checkpoint/optimizer-state savings.
- Minor typos/style: “Supra-Mag denotes…” appears before formal definition in the intro tables; “SpA” is introduced then Super is used; ensure consistent method naming (Super vs Super-Tuning title).
Circularity Check
No circular derivation: Super/Supra are empirical PEFT methods whose accuracy claims are measured outcomes, not quantities forced by their own selection scores or budget rules.
full rationale
This paper does not claim a first-principles prediction that reduces to its inputs. Super fixes a sparse support via a Wanda-style score A_ij = |W_ij|∥X_j:∥_2 from a calibration pass (Algorithm 1, Eq. 7–9); Supra adds LoRA under an explicit budget split λ and rank conversion r_i = ⌊λ T_i/(c_i+b_i)⌋ (Eq. 14–22). Proposition 3.1 is a correct single-weight reconstruction identity used only to motivate a training-free ordering heuristic; the paper explicitly states the score is not an optimality criterion for sparse fine-tuning and that learned deltas are unconstrained. Reported accuracies are external measurements on held-out arithmetic benchmarks after Math17K training under matched scalar budgets, with LR chosen on validation NLL—not quantities reconstructed from the mask scores. Related work (Wanda, LoRA, PaFi, RoSA, SIFT) is cited from external authors; there is no load-bearing self-citation uniqueness chain, no fitted constant renamed as a prediction of the main claim, and no renaming of a known closed-form result. Schedule/variant selection in compact Tables 1–2 is a reporting protocol issue (fairness of comparison), not circular reasoning by construction. Score 0 is appropriate.
Axiom & Free-Parameter Ledger
free parameters (5)
- rank-equivalent budget r0
- Supra low-rank budget fraction λ
- validation-selected learning rate
- training schedule (1 vs 3 epochs)
- Wanda calibration set size/source
axioms (4)
- domain assumption Wanda single-weight reconstruction identity (Prop. 3.1) is a useful training-free ordering heuristic for sparse fine-tuning supports, not an optimality criterion for learned deltas.
- domain assumption Matching trainable scalar-parameter counts is a fair primary PEFT comparison axis even when memory/runtime differ by implementation.
- domain assumption Held-out Math17K validation NLL is an adequate selector of learning rate and checkpoint for arithmetic exact-answer evaluation.
- standard math Standard linear algebra and PEFT parameterizations (LoRA rank, sparse support cardinality, Hadamard mask updates).
invented entities (2)
-
Super (Wanda-ordered fixed sparse PEFT)
independent evidence
-
Supra (budget-matched Super+LoRA hybrid)
independent evidence
read the original abstract
Large language models (LLMs) remain expensive to fine-tune because full-parameter updates require substantial memory, compute, and per-task storage. We study whether saliency signals originally developed for pruning can be reused to choose where a model should adapt. We propose Super, a sparse parameter-efficient fine-tuning (PEFT) method that fixes a small trainable support using a Wanda-style activation-weighted magnitude score [Sun et al., 2023] computed from a calibration pass. We then introduce Supra, a hybrid adapter that combines this sparse update with LoRA while preserving a matched trainable-parameter budget through a simple budget-splitting rule. In single-seed Math17K arithmetic experiments on Llama-3.2-1B and Meta-Llama-3-8B, the best Super/Supra variants achieve the highest average accuracy among the tested schedule-selected adapter configurations. We also include a PaFi-style magnitude-only support as a closest training-free sparse baseline and find that low-score supports under both magnitude and Wanda-style orderings can be effective. These results suggest that simple pruning-inspired orderings can provide useful fixed sparse supports for PEFT, especially when combined with low-rank adapters.
Figures
Reference graph
Works this paper leans on
-
[1]
Scaling sparse fine-tuning to large language models.arXiv preprint arXiv:2401.16405,
Alan Ansell, Ivan Vuli ´c, Hannah Sterz, Anna Korhonen, and Edoardo M Ponti. Scaling sparse fine-tuning to large language models.arXiv preprint arXiv:2401.16405,
-
[2]
Gallop: Gradient-based sparse learning on low-magnitude parameters.arXiv preprint arXiv:2510.19778,
Anand Choudhary, Yasser Sulaıman, Lukas Mauch, Ghouthi Boukli Hacene, Fabien Cardinaux, and Antoine Bosselut. Gallop: Gradient-based sparse learning on low-magnitude parameters.arXiv preprint arXiv:2510.19778,
-
[3]
doi: 10.48550/arXiv.2510.19778. Karl Cobbe, Vineet Kosaraju, Mohammad Bavarian, Mark Chen, Heewoo Jun, Lukasz Kaiser, Matthias Plappert, Jerry Tworek, Jacob Hilton, Reiichiro Nakano, et al. Training verifiers to solve math word problems.arXiv preprint arXiv:2110.14168,
-
[4]
Sltrain: a sparse plus low-rank approach for parameter and memory efficient pretraining
Andi Han, Jiaxiang Li, Wei Huang, Mingyi Hong, Akiko Takeda, Pratik Jawanpuria, and Bamdev Mishra. Sltrain: a sparse plus low-rank approach for parameter and memory efficient pretraining. arXiv preprint arXiv:2406.02214,
-
[5]
Learning to solve arithmetic word problems with verb categorization
Mohammad Javad Hosseini, Hannaneh Hajishirzi, Oren Etzioni, and Nate Kushman. Learning to solve arithmetic word problems with verb categorization. InProceedings of the 2014 conference on empirical methods in natural language processing (EMNLP), pages 523–533,
2014
-
[6]
Lora: Low-rank adaptation of large language models.arXiv preprint arXiv:2106.09685,
Edward J Hu, Yelong Shen, Phillip Wallis, Zeyuan Allen-Zhu, Yuanzhi Li, Shean Wang, Lu Wang, and Weizhu Chen. Lora: Low-rank adaptation of large language models.arXiv preprint arXiv:2106.09685,
-
[7]
Cen-Jhih Li and Aditya Bhaskara. An efficient sparse fine-tuning with low quantization error via neural network pruning.arXiv preprint arXiv:2502.11439,
-
[8]
Wang Ling, Dani Yogatama, Chris Dyer, and Phil Blunsom. Program induction by rationale genera- tion: Learning to solve and explain algebraic word problems.arXiv preprint arXiv:1705.04146,
-
[9]
Dora: Weight-decomposed low-rank adaptation.arXiv preprint arXiv:2402.09353,
Shih-Yang Liu, Chien-Yi Wang, Hongxu Yin, Pavlo Molchanov, Yu-Chiang Frank Wang, Kwang- Ting Cheng, and Min-Hung Chen. Dora: Weight-decomposed low-rank adaptation.arXiv preprint arXiv:2402.09353,
-
[10]
URL https://aclanthology. org/2025.acl-long.1541/. 16 Da Ma, Lu Chen, Pengyu Wang, Hongshen Xu, Hanqi Li, Liangtai Sun, Su Zhu, Shuai Fan, and Kai Yu. Sparsity-accelerated training for large language models.arXiv preprint arXiv:2406.01392,
Pith/arXiv arXiv 2025
-
[11]
Mahdi Nikdan, Soroush Tabesh, Elvir Crnˇcevi´c, and Dan Alistarh. Rosa: Accurate parameter-efficient fine-tuning via robust adaptation.arXiv preprint arXiv:2401.04679,
-
[12]
Are nlp models really able to solve simple math word problems?arXiv preprint arXiv:2103.07191,
Arkil Patel, Satwik Bhattamishra, and Navin Goyal. Are nlp models really able to solve simple math word problems?arXiv preprint arXiv:2103.07191,
-
[13]
Solving general arithmetic word problems.arXiv preprint arXiv:1608.01413,
Subhro Roy and Dan Roth. Solving general arithmetic word problems.arXiv preprint arXiv:1608.01413,
-
[14]
Sparse is enough in fine-tuning pre-trained large language models.arXiv preprint arXiv:2312.11875,
Weixi Song, Zuchao Li, Lefei Zhang, Hai Zhao, and Bo Du. Sparse is enough in fine-tuning pre-trained large language models.arXiv preprint arXiv:2312.11875,
-
[15]
A simple and effective pruning approach for large language models.arXiv preprint arXiv:2306.11695,
Mingjie Sun, Zhuang Liu, Anna Bair, and J Zico Kolter. A simple and effective pruning approach for large language models.arXiv preprint arXiv:2306.11695,
-
[16]
Haoyun Xu, Runzhe Zhan, Derek F Wong, and Lidia S Chao. Let’s focus on neuron: Neuron-level supervised fine-tuning for large language model.arXiv preprint arXiv:2403.11621,
-
[17]
S2ft: Efficient, scalable and generalizable llm fine-tuning by structured sparsity
Xinyu Yang, Jixuan Leng, Geyang Guo, Jiawei Zhao, Ryumei Nakada, Linjun Zhang, Huaxiu Yao, and Beidi Chen. S2ft: Efficient, scalable and generalizable llm fine-tuning by structured sparsity. arXiv preprint arXiv:2412.06289,
-
[18]
Adaptive budget allocation for parameter-efficient fine-tuning.arXiv preprint arXiv:2303.10512,
Qingru Zhang, Minshuo Chen, Alexander Bukharin, Nikos Karampatziakis, Pengcheng He, Yu Cheng, Weizhu Chen, and Tuo Zhao. Adaptive budget allocation for parameter-efficient fine-tuning.arXiv preprint arXiv:2303.10512,
-
[19]
Maxim Zhelnin, Viktor Moskvoretskii, Egor Shvetsov, Egor Venediktov, Mariya Krylova, Aleksandr Zuev, and Evgeny Burnaev. Gift-sw: Gaussian noise injected fine-tuning of salient weights for llms.arXiv preprint arXiv:2408.15300,
-
[20]
All trainable masks use C4 calibration and approximately 5.6M trainable sparse parameters
The Base row is frozen. All trainable masks use C4 calibration and approximately 5.6M trainable sparse parameters. Best average within each epoch block is bold. Results are exact-answer accuracy (%). Method EpochsβSelected LR AddSub MultiArith SingleEq GSM8K AQuA SV AMP Average BASE(frozen) – – – 13.67 4.67 21.46 2.81 21.65 11.60 12.64 Super(TopK) 1 1.05·...
2050
-
[21]
Full fine-tuning is an unbudgeted reference row separated by rules
The Base row is frozen. Full fine-tuning is an unbudgeted reference row separated by rules. Bold marks the lowest matched-budget adapter average PPL. TheCalib.column gives the calibration source used to construct fixedWanda-style sparse supports; “–” denotes methods that do not use a calibration pass. Lower is better. Perplexities are computed on up to 12...
2000
-
[22]
Each row uses the learning rate selected by the held-out validation split of the fine-tuning set
Adapter rows use approximately the rank-8LoRAtrainable-parameter budget for this model. Each row uses the learning rate selected by the held-out validation split of the fine-tuning set. Results are exact-answer accuracy (%). Method Calib. Selected LR AddSub MultiArith SingleEq GSM8K AQuA SV AMP Average BASE(frozen) – – 22.53 21.00 36.42 10.24 24.02 24.10 ...
2072
-
[23]
Lower is better
TheCalib.column gives the calibration source used to construct fixedWanda-style sparse supports; “–” denotes methods that do not use a calibration pass. Lower is better. Perplexities are computed on up to 120 examples per benchmark. Method Calib. Selected LR AddSub MultiArith SingleEq GSM8K AQuA SV AMP Average BASE(frozen) – – 2.15 2.28 2.30 1.98 2.64 2.4...
2079
discussion (0)
Sign in with ORCID, Apple, or X to comment. Anyone can read and Pith papers without signing in.