Papers › MaskLLM: Learnable Semi-Structured Sparsity for Large Language Models

MaskLLM: Learnable Semi-Structured Sparsity for Large Language Models

26 Sep 2024arXiv:2409.17481archive 2025-07-28

Gongfan Fang, Hongxu Yin, Saurav Muralidharan, Greg Heinrich, Jeff Pool, Jan Kautz, Pavlo Molchanov, Xinchao Wang

Large Language Models (LLMs) are distinguished by their massive parameter counts, which typically result in significant redundancy. This work introduces MaskLLM, a learnable pruning method that establishes Semi-structured (or ``N:M'') Sparsity in LLMs, aimed at reducing computational overhead during inference. Instead of developing a new importance criterion, MaskLLM explicitly models N:M patterns as a learnable distribution through Gumbel Softmax sampling. This approach facilitates end-to-end training on large-scale datasets and offers two notable advantages: 1) High-quality Masks - our method effectively scales to large datasets and learns accurate masks; 2) Transferability - the probabilistic modeling of mask distribution enables the transfer learning of sparsity across domains or tasks. We assessed MaskLLM using 2:4 sparsity on various LLMs, including LLaMA-2, Nemotron-4, and GPT-3, with sizes ranging from 843M to 15B parameters, and our empirical results show substantial improvements over state-of-the-art methods. For instance, leading approaches achieve a perplexity (PPL) of 10 or greater on Wikitext compared to the dense model's 5.12 PPL, but MaskLLM achieves a significantly lower 6.72 PPL solely by learning the masks with frozen weights. Furthermore, MaskLLM's learnable nature allows customized masks for lossless application of 2:4 sparsity to downstream tasks or domains. Code is available at https://github.com/NVlabs/MaskLLM.

PaperPDFCodeCode Syntology ran

In Syntology Open this paper in Syntology's Atlas, the map of the papers in Syntology's graph and their citations.

For agents, Syntology's MCP tool lists every function and class Syntology harvested from this paper and whether it ran (how to connect): get_harvested_code_for_paper(arxiv_id="2409.17481")

Code

Syntology Ran 5 of 16 code samples harvested from 1 repository linked to this paper; 11 have no recorded run. Of those that ran: 5 ran with no contract checked.

By repository: official repository: 16 samples from 1 repository, 5 ran. The run record, sample by sample. “Ran” means executed on a synthesized input, not that the code is correct or reproduces the paper.

nvlabs/maskllm officialmentioned in papermentioned on GitHubpytorchNOASSERTION report

Repository list and official/mentioned flags are the archive's, frozen 2025-07-28. Reachability, where shown, is from one Syntology probe window (2026-09-16 to 2026-09-18); repositories not probed show nothing. GitHub stars are not tracked.

Code Syntology ran Syntology

16 samples harvested; 5 ran; 0 honoured the contract we drafted; 11 have no recorded run. Read from Syntology's graph 2026-09-24; that is when this build read the record, not when the samples ran.

5ran
11unverified

Licence: 16 of the 16 samples are pointer only, meaning Syntology does not serve that copy's text. This page shows no code text for any sample; each one links to its file in the repository.

Harvested from nvlabs/maskllm. “Ran” means the sample executed on a synthesized input. It does not mean the output is correct, and nothing here reproduces the paper's results. “Honoured” and “violated” refer to a contract Syntology drafted from the code itself; “our draft was wrong” and “fixture could not drive it” are failures of Syntology's instrument, not of the code.

Each sample ends with its code_sha256, Syntology's identity for that exact code. An agent fetches the stored sample with Syntology's MCP tool get_code(code_sha256="…") (how to connect); click an identity to copy that call.

Repository labels, per sample. official repository: The archive marks this repository official for the paper. named in the paper: The archive records that the paper mentions this repository; it is not marked official. community (archive-listed): In the archive's code links for this paper, not marked official and not recorded as mentioned in the paper. found in paper text by Syntology: Syntology found this repository in the paper's own text; whether it is the authors' implementation is not asserted. community: Not in the archive's code links for this paper; a community repository Syntology harvested. Samples from a repository marked official are listed first. Licence labels name the repository's licence as recorded at harvest. “Pointer only” means Syntology does not serve that copy's text, for one of four reasons: no licence file was found; the licence was not identified; the licence is recorded as permissive but that copy's record is not marked cleared; or the licence is outside the permissive list Syntology serves text under (MIT, Apache-2.0, BSD and similar). Some licences outside that list permit redistribution, such as WTFPL, and GPL-3.0 under its conditions; they are simply not on the list. Hover a licence label for the reason. File links open the file on GitHub at the default branch, which may have changed since the harvest.

CudaRNGStatesTracker nvlabs/maskllm/learnable_sparsity/differentiable_mask.py official repository ran licence not identified · pointer only · 3a4d0d8bbbbf7679 · report
get_cuda_rng_tracker nvlabs/maskllm/learnable_sparsity/differentiable_mask.py official repository ran licence not identified · pointer only · 7073cc1e555d6836 · report
get_expert_parallel_rng_tracker_name nvlabs/maskllm/learnable_sparsity/differentiable_mask.py official repository ran licence not identified · pointer only · 8d9516b99abbc7b5 · report
get_llm NVlabs/MaskLLM/tool_compute_mask_hf.py official repository ran licence not identified · pointer only · 1b16cd00fbac2ce5 · report
get_wikitext2 NVlabs/MaskLLM/eval_llama_ppl.py official repository ran no licence file found · pointer only · dee8be97b2cf4692 · report
DifferentiableMask nvlabs/maskllm/learnable_sparsity/differentiable_mask.py official repository unverified licence not identified · pointer only · 3feb197bb2f80c7c · report
_ensure_var_is_initialized nvlabs/maskllm/learnable_sparsity/differentiable_mask.py official repository unverified licence not identified · pointer only · 20d99399acdd4df8 · report
_initialize_affine_weight_gpu nvlabs/maskllm/learnable_sparsity/differentiable_mask.py official repository unverified licence not identified · pointer only · 6cd59afbca9bb213 · report
_set_cuda_rng_state nvlabs/maskllm/learnable_sparsity/differentiable_mask.py official repository unverified licence not identified · pointer only · bbfbfd2fc26ae9c4 · report
get_args nvlabs/maskllm/learnable_sparsity/differentiable_mask.py official repository unverified licence not identified · pointer only · d25230985eb2b130 · report
get_c4 NVlabs/MaskLLM/eval_llama_ppl.py official repository unverified no licence file found · pointer only · 7630a157a3b32ab9 · report
get_loaders NVlabs/MaskLLM/eval_llama_ppl.py official repository unverified licence not identified · pointer only · a6cf7a5e8f29a402 · report
load_checkpoint_to_model NVlabs/MaskLLM/tool_export_to_hf.py official repository unverified licence not identified · pointer only · 91e00b8286e04fd0 · report
parse_args NVlabs/MaskLLM/megatron/arguments.py official repository unverified licence not identified · pointer only · f2ce3a79ab6a26c5 · report
print_rank_0 nvlabs/maskllm/learnable_sparsity/differentiable_mask.py official repository unverified licence not identified · pointer only · 44ee8f559edfd194 · report
set_tensor_model_parallel_attributes nvlabs/maskllm/learnable_sparsity/differentiable_mask.py official repository unverified licence not identified · pointer only · 5c24809f67be0e0a · report

Tasks

Large Language ModelModel CompressionNetwork PruningTransfer Learning

Results from the paper archive 2025-07-28

No leaderboard rows for this paper in the archive.

Methods

AdamAttentionAttention DropoutBPECosine AnnealingDense ConnectionsDropoutGPT-3Gumbel SoftmaxLayer NormalizationLinear LayerLinear Warmup With Cosine AnnealingMulti-Head AttentionPruningResidual ConnectionSoftmaxWeight Decay

Report a problem or propose a change · a person checks every report against the paper or source before anything changes; decisions are listed on /corrections