Globally optimized SVD compression of LLMs via Fermi-function-based rank selection and gauge fixing
- URL: http://arxiv.org/abs/2512.03062v1
- Date: Wed, 26 Nov 2025 10:54:01 GMT
- Title: Globally optimized SVD compression of LLMs via Fermi-function-based rank selection and gauge fixing
- Authors: Roman Rausch, David Jansen, Sukhbinder Singh, Román Orús,
- Abstract summary: Low-rank decompositions of Large Language Models (LLMs) are very demanding in terms of their computational resources.<n>We present two physics-inspired improvements to SVD compression: textbfFermiGrad, a gradient-descent algorithm that determines globally optimal layer-wise ranks, and textbfPivGa, an additional textitlossless compression of the low-rank factors.
- Score: 0.0
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: Large Language Models (LLMs) are very demanding in terms of their computational resources. Low-rank decompositions of LLM weights, e.g. via Singular Value Decomposition (SVD), is a promising approach for LLM compression, but presents several practical hurdles, e.g. selecting appropriate layer-wise ranks and getting rid of its parameter redundancy. In this work, we present two physics-inspired improvements to SVD LLM compression: (1) \textbf{FermiGrad}, a gradient-descent algorithm that determines globally optimal layer-wise ranks by relaxing the discrete singular-value truncation into a continuous optimization using the Fermi function; (2) \textbf{PivGa}, an additional \textit{lossless} compression of the low-rank factors that exploits the intrinsic gauge freedom in their parametrization.
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