A Survey on LLM Test-Time Compute via Search: Tasks, LLM Profiling, Search Algorithms, and Relevant Frameworks
Xinzhe Li
TL;DR
The paper addresses the challenge of comparing LLM inference via search (LIS) frameworks by presenting a unified MDP-based task formulation, modular LLM-Profiled Roles (policy, evaluator, transition model), and reusable search procedures. It surveys 11 LIS frameworks, analyzes deviations from classical search algorithms, and discusses applicability, performance, and efficiency, including open issues like action undoing and irreversible actions. The work proposes an interchangeable, object-oriented interface to enable fair comparisons and future extensibility, and it highlights practical considerations such as computation cost, memory, and potential for parallel research. Together, these contributions offer a structured blueprint for designing, evaluating, and extending LIS systems in language reasoning, web navigation, graph traversal, and tool-based tasks with LLMs. The paper thus serves as a foundational reference for researchers and engineers building and benchmarking test-time compute via search in real-world LLM applications.
Abstract
LLM test-time compute (or LLM inference) via search has emerged as a promising research area with rapid developments. However, current frameworks often adopt distinct perspectives on three key aspects: task definition, LLM profiling, and search procedures, making direct comparisons challenging. Moreover, the search algorithms employed often diverge from standard implementations, and their specific characteristics are not thoroughly specified. This survey aims to provide a comprehensive but integrated technical review on existing LIS frameworks. Specifically, we unify task definitions under Markov Decision Process (MDP) and provides modular definitions of LLM profiling and search procedures. The definitions enable precise comparisons of various LLM inference frameworks while highlighting their departures from conventional search algorithms. We also discuss the applicability, performance, and efficiency of these methods. For ongoing paper updates, please refer to our GitHub repository: https://github.com/xinzhel/LLM-Search.
