Pith. sign in

REVIEW 26 cited by

TreePO: Bridging the Gap of Policy Optimization and Efficacy and Inference Efficiency with Heuristic Tree-based Modeling

Not yet reviewed by Pith; the record is open.

This paper has not been read by Pith yet. Machine review is queued; the pith claim, tier, and objections will appear here once it completes.

SPECIMEN: schema-true, not a live event

T0 review · schema-true

One-sentence machine reading of the paper's core claim.

pith:XXXXXXXX · record.json · timestamp

arxiv 2508.17445 v1 pith:ZU2Y5F6B submitted 2025-08-24 cs.LG cs.CL

TreePO: Bridging the Gap of Policy Optimization and Efficacy and Inference Efficiency with Heuristic Tree-based Modeling

classification cs.LG cs.CL
keywords treeposamplingcomputeefficiencymodelspolicyreasoningalgorithm
verification ladder T0 review T1 audit T2 compute T3 formal T4 reserved
0 comments
Share X Bluesky LinkedIn Reddit HN
read the original abstract

Recent advancements in aligning large language models via reinforcement learning have achieved remarkable gains in solving complex reasoning problems, but at the cost of expensive on-policy rollouts and limited exploration of diverse reasoning paths. In this work, we introduce TreePO, involving a self-guided rollout algorithm that views sequence generation as a tree-structured searching process. Composed of dynamic tree sampling policy and fixed-length segment decoding, TreePO leverages local uncertainty to warrant additional branches. By amortizing computation across common prefixes and pruning low-value paths early, TreePO essentially reduces the per-update compute burden while preserving or enhancing exploration diversity. Key contributions include: (1) a segment-wise sampling algorithm that alleviates the KV cache burden through contiguous segments and spawns new branches along with an early-stop mechanism; (2) a tree-based segment-level advantage estimation that considers both global and local proximal policy optimization. and (3) analysis on the effectiveness of probability and quality-driven dynamic divergence and fallback strategy. We empirically validate the performance gain of TreePO on a set reasoning benchmarks and the efficiency saving of GPU hours from 22\% up to 43\% of the sampling design for the trained models, meanwhile showing up to 40\% reduction at trajectory-level and 35\% at token-level sampling compute for the existing models. While offering a free lunch of inference efficiency, TreePO reveals a practical path toward scaling RL-based post-training with fewer samples and less compute. Home page locates at https://m-a-p.ai/TreePO.

discussion (0)

Sign in with ORCID, Apple, or X to comment. Anyone can read and Pith papers without signing in.

Forward citations

Cited by 26 Pith papers

Reviewed papers in the Pith corpus that reference this work. Sorted by Pith novelty score.

  1. Efficient and Trainable Language Model Test-Time Scaling via Local Branch Routing

    cs.CL 2026-06 unverdicted novelty 7.0

    LBR performs token-level test-time scaling via local branch routing on hidden states, enabling end-to-end RL training and improving Pass@1 and Pass@32 on math benchmarks over CoT and RLVR baselines.

  2. Efficient and Trainable Language Model Test-Time Scaling via Local Branch Routing

    cs.CL 2026-06 unverdicted novelty 7.0

    Local Branch Routing (LBR) is a token-level framework for test-time scaling in language models that uses local branch hidden states for routing and supports end-to-end RL, showing gains in Pass@1 and Pass@32 on math r...

  3. StepCodeReasoner: Aligning Code Reasoning with Stepwise Execution Traces via Reinforcement Learning

    cs.SE 2026-05 unverdicted novelty 7.0

    StepCodeReasoner aligns code reasoning with verifiable stepwise execution traces via print anchors and bi-level GRPO reinforcement learning, reaching SOTA results on CRUXEval (91.1%) and LiveCodeBench (86.5%) for a 7B model.

  4. Generate, Filter, Control, Replay: A Comprehensive Survey of Rollout Strategies for LLM Reinforcement Learning

    cs.LG 2026-04 unverdicted novelty 7.0

    This survey introduces the Generate-Filter-Control-Replay (GFCR) taxonomy to structure rollout pipelines for RL-based post-training of reasoning LLMs.

  5. On the Overscaling Curse of Parallel Thinking: System Efficacy Contradicts Sample Efficiency

    cs.LG 2026-01 unverdicted novelty 7.0

    Parallel thinking in LLMs suffers from overscaling where fixed global budgets waste samples; LanBo predicts per-sample budgets from latent states to raise utilization without hurting accuracy.

  6. From Reasoning Traces to Reusable Modules: Understanding Compositional Generalization in Language Model Reasoning

    cs.LG 2026-06 conditional novelty 6.5

    SFT supplies entangled compositional traces of atomic skills and routing modules; RL identifies those modules and enables recombination on novel compositions outside the SFT support.

  7. Beyond the Mean: Multi-Moment Policy Optimization for LLM Reasoning

    cs.AI 2026-08 conditional novelty 6.0

    MMPO jointly minimizes the first T moments of the per-problem failure-probability distribution — equivalent to minimizing expected truncated time to first success — and reports average gains over single-moment RL obje...

  8. Off-Context GRPO: Learning to Reason on Hard Problems using Privileged Information

    cs.LG 2026-07 conditional novelty 6.0

    OC-GRPO reweights GRPO gradients with an importance ratio so that hints used during rollout generation still optimize the original unguided objective, delivering a 13.8% relative Pass@1 gain over vanilla GRPO.

  9. Distilled Reinforcement Learning for LLM Post-training

    cs.LG 2026-07 conditional novelty 6.0

    Using teacher preferences to reweight RL gradients only on correct responses improves LLM post-training on math and knowledge benchmarks in both within- and cross-family settings.

  10. Learning with a Single Rollout via Monte Carlo Pass@k Critic

    cs.LG 2026-06 unverdicted novelty 6.0

    SR-PPO trains a Pass@k critic from single-rollout Monte Carlo outcomes to enable token-level advantage estimation in language model RL, yielding stable training and Pass@128 gains on math benchmarks.

  11. From Reasoning Traces to Reusable Modules: Understanding Compositional Generalization in Language Model Reasoning

    cs.LG 2026-06 unverdicted novelty 6.0

    Introduces a hierarchical latent selection model showing SFT supplies raw module materials in compound traces while RL decomposes them to identify atomic modules and enable recombination for new reasoning configurations.

  12. When to Stop Reusing: Dynamic Gradient Gating for Sample-Efficient RLVR

    cs.LG 2026-05 unverdicted novelty 6.0

    Dynamic Gradient Gating monitors lm_head gradient norms to safely reuse rollout batches in RLVR, achieving up to 2.93x sample efficiency and 2.14x wall-clock speedup across math, ALFWorld, WebShop, and QA tasks.

  13. Confidence-Aware Alignment Makes Reasoning LLMs More Reliable

    cs.AI 2026-05 unverdicted novelty 6.0

    CASPO trains LLMs via iterative direct preference optimization so that token-level confidence tracks step-wise correctness, then applies Confidence-aware Thought pruning at inference to improve both reliability and sp...

  14. Tree-based Credit Assignment for Multi-Agent Memory System

    cs.MA 2026-05 unverdicted novelty 6.0

    TreeMem assigns credit to agents in multi-agent memory systems by expanding outputs into a tree and using Monte Carlo averaging of final rewards to optimize each agent's policy.

  15. Agent-World: Scaling Real-World Environment Synthesis for Evolving General Agent Intelligence

    cs.AI 2026-04 unverdicted novelty 6.0

    Agent-World autonomously synthesizes verifiable real-world tasks and uses continuous self-evolution to train 8B and 14B agents that outperform proprietary models on 23 benchmarks.

  16. MARS$^2$: Scaling Multi-Agent Tree Search via Reinforcement Learning for Code Generation

    cs.AI 2026-04 unverdicted novelty 6.0

    MARS² integrates multi-agent collaboration with tree-structured search in RL to boost code generation by increasing exploratory diversity and using path-level group advantages for credit assignment.

  17. Tree Training: Accelerating Agentic LLMs Training via Shared Prefix Reuse

    cs.LG 2025-11 unverdicted novelty 6.0

    Tree Training serializes tree trajectories via DFS and uses redundancy-free partitioning to compute weighted per-token losses exactly once per token, achieving up to 6.2x training speedup on dense and MoE models.

  18. The Landscape of Agentic Reinforcement Learning for LLMs: A Survey

    cs.AI 2025-09 accept novelty 6.0

    Survey that defines agentic RL for LLMs via POMDPs, introduces a taxonomy of planning/tool-use/memory/reasoning capabilities and domains, and compiles open environments from over 500 papers.

  19. Process Reward Informed Tree Rollout for Effective Multi-Turn RL

    cs.CL 2026-07 conditional novelty 5.0

    Using process feedback to guide which partial trajectories to branch on, PATR replaces uniform independent rollouts with adaptive tree rollouts for multi-turn agent RL, reporting +5.0 points on SWE-Bench and +9.3 on F...

  20. Modularized Reinforcement Learning on LLMs: From MDP Creation to Exploration and Learning

    cs.LG 2026-06 unverdicted novelty 5.0

    Survey mapping RL techniques onto LLM training and highlighting gaps in value-based, off-policy, and bootstrapping methods.

  21. Trust Region On-Policy Distillation

    cs.LG 2026-05 unverdicted novelty 5.0

    TrOPD stabilizes on-policy distillation for LLMs with trust-region learning, outlier estimation, and off-policy guidance, outperforming prior OPD methods on reasoning and code benchmarks.

  22. Plan Then Action:High-Level Planning Guidance Reinforcement Learning for LLM Reasoning

    cs.AI 2025-10 conditional novelty 5.0

    A plan-then-reason SFT plus a plan-quality reward in GRPO improves math-reasoning accuracy by small but consistent margins over GRPO and DAPO.

  23. Rethinking Agentic Reinforcement Learning In Large Language Models

    cs.AI 2026-04 unverdicted novelty 3.0

    The paper reviews conceptual foundations, methodological innovations, effective designs, critical challenges, and future directions for LLM-based Agentic Reinforcement Learning.

  24. A Survey of Reinforcement Learning for Large Reasoning Models

    cs.CL 2025-09 accept novelty 3.0

    A survey compiling RL methods, challenges, data resources, and applications for enhancing reasoning in large language models and large reasoning models since DeepSeek-R1.

  25. Rethinking Agentic Reinforcement Learning In Large Language Models

    cs.AI 2026-04 unverdicted novelty 2.0

    The paper surveys the conceptual foundations, methodological innovations, challenges, and future directions of agentic reinforcement learning frameworks that embed cognitive capabilities like meta-reasoning and self-r...

  26. Rethinking Agentic Reinforcement Learning In Large Language Models

    cs.AI 2026-04 unverdicted novelty 2.0

    This review synthesizes conceptual foundations, methods, challenges, and future directions for agentic reinforcement learning in large language models.