Open Brain
arXivPaperNeeds Review

MuonGS: Pretraining LLMs with Relaxed Weight-Norm Control

MuonGS changes Muon pretraining by projecting out each update’s radial component without fixing weight norms. It reports lower long-run validation perplexity than MuonH, including an estimated 15% token-equivalent speedup in one dense-model comparison.

arXiv · Oct 27, 2026
Open Source Open MarkdownOpen JSON
Source Summary

MuonGS uses a Gram–Schmidt projection to remove the radial part of each Muon update without fixing the weight norm. The paper proves a **√t** upper bound on norm growth under stated conditions and reports up to **15%** estimated token-equivalent speedup at matched validation loss in a dense model.

Practical Implication

For teams training language models, MuonGS is an optimizer candidate to compare when long training horizons matter. The reported experiments include dense models at **160M and 400M parameters** and a **135M-active / 1B-total MoE** model.

Agent-Ready Context
MuonGS uses a Gram–Schmidt projection to remove the radial part of each Muon update without fixing the weight norm. The paper proves a **√t** upper bound on norm growth under stated conditions and reports up to **15%** estimated token-equivalent speedup at matched validation loss in a dense model.

For teams training language models, MuonGS is an optimizer candidate to compare when long training horizons matter. The reported experiments include dense models at **160M and 400M parameters** and a **135M-active / 1B-total MoE** model.

The speedup is an estimate from one dense-model comparison, and the theoretical guarantees depend on stated assumptions. The material does not establish that the result transfers to other architectures or training setups.
Connected Context · Feed7 Judgment

MuonGS offers a way to limit optimizer-driven norm growth without fixing weight norms, with a reported token-equivalent speedup in a bounded set of model experiments. The result makes optimizer choice worth comparing for long training runs, but does not establish that the gain transfers across architectures or setups.

Context Map
modelresearchdata#open-models#model-selection
Uncertainty
The speedup is an estimate from one dense-model comparison, and the theoretical guarantees depend on stated assumptions. The material does not establish that the result transfers to other architectures or training setups.