PulseAugur
EN
LIVE 23:00:32

GRPO fine-tuning yields mixed results across three LLMs

A machine learning practitioner experimented with applying the GRPO (Proximal Policy Optimization) algorithm to three large language models of varying sizes, trained from scratch. While pre-training showed expected improvements with scale, the GRPO fine-tuning phase yielded inconsistent and sometimes detrimental results. The smallest model (353M parameters) showed minimal impact, while a slightly smaller model (316M parameters) experienced a significant performance drop in perplexity, and the largest model (672M parameters) saw a minor degradation. AI

IMPACT Inconsistent results from GRPO fine-tuning suggest further research is needed to understand its application across different model scales and training setups.

RANK_REASON The item details an experiment with a specific LLM training technique (GRPO) and its outcomes on different model sizes, which falls under research. [lever_c_demoted from research: ic=1 ai=1.0]

Read on r/MachineLearning →

AI-generated summary · Google Gemini · from 1 sources. How we write summaries →

GRPO fine-tuning yields mixed results across three LLMs

COVERAGE [1]

  1. r/MachineLearning TIER_1 English(EN) · /u/john_enev ·

    Same GRPO recipe on three from-scratch LLMs (353M/316M/672M) gave three different outcomes, with no clean relationship to scale [P]

    <!-- SC_OFF --><div class="md"><p>I trained three LLMs from scratch in raw PyTorch then post-trained each one with SFT and then GRPO. Same process every time: same synthetic arithmetic curriculum, same reward function, same hyperparameters, same KL coefficient.</p> <p>Pre-trainin…