OckBench: Measuring the Efficiency of LLM Reasoning
Zheng Du, Hao Kang, Song Han, Tushar Krishna, Ligeng Zhu
TL;DR
The paper addresses the gap in LLM evaluation where efficiency of reasoning, measured by decoding token count, is overlooked in favor of accuracy. It introduces OckBench, a model- and hardware-agnostic benchmark that jointly measures accuracy and token consumption in math and coding tasks, enabling analysis of accuracy–efficiency trade-offs across diverse models. The authors formalize decoding token count as an intrinsic efficiency metric and demonstrate Pareto-frontier style comparisons across 16 models, revealing substantial token-efficiency differences even among models with similar accuracy. The results underscore token efficiency as a practical concern for latency, energy use, and cost in real deployments, and the work provides a reproducible platform to drive the design of more token-efficient reasoning systems. Future directions include dynamic reasoning budgets, early-exit strategies, and expanded benchmarks to broader real-world workloads.
Abstract
Large language models such as GPT-4, Claude 3, and the Gemini series have improved automated reasoning and code generation. However, existing benchmarks mainly focus on accuracy and output quality, and they ignore an important factor: decoding token efficiency. In real systems, generating 10,000 tokens versus 100,000 tokens leads to large differences in latency, cost, and energy. In this work, we introduce OckBench, a model-agnostic and hardware-agnostic benchmark that evaluates both accuracy and token count for reasoning and coding tasks. Through experiments comparing multiple open- and closed-source models, we uncover that many models with comparable accuracy differ wildly in token consumption, revealing that efficiency variance is a neglected but significant axis of differentiation. We further demonstrate Pareto frontiers over the accuracy-efficiency plane and argue for an evaluation paradigm shift: we should no longer treat tokens as "free" to multiply. OckBench provides a unified platform for measuring, comparing, and guiding research in token-efficient reasoning. Our benchmarks are available at https://ockbench.github.io/ .
