RouterEval: A Comprehensive Benchmark for Routing LLMs to Explore Model-level Scaling Up in LLMs

Routing large language models (LLMs) is a novel paradigm that recommends the most suitable LLM from a pool of candidates to process a given input through a well-designed router. Our comprehensive analysis reveals a model-level scaling-up phenomenon in LLMs, i.e., a capable router can significantly enhance the performance of this paradigm as the number of candidates increases. This improvement can even easily surpass the performance of the best single model in the pool and most existing strong LLMs, making it a highly promising paradigm. However, the lack of comprehensive and open-source benchmarks for Routing LLMs has hindered the development of routers. In this paper, we introduce RouterEval, a benchmark designed specifically for router research, which includes over 200,000,000 performance records for 12 popular LLM evaluations across areas such as knowledge-based Q&A, commonsense reasoning, semantic understanding, mathematical reasoning, and instruction following, based on more than 8,500 LLMs. Using RouterEval, extensive evaluations of existing Routing LLM methods reveal that most still have significant room for improvement. See https://github.com/MilkThink-Lab/RouterEval for all data, code, and tutorials.