| | --- |
| | base_model: |
| | - Qwen/Qwen3-8B-Base |
| | datasets: |
| | - Suu/KlearReasoner-MathSub-30K |
| | - Suu/KlearReasoner-CodeSub-15K |
| | language: |
| | - en |
| | license: apache-2.0 |
| | metrics: |
| | - accuracy |
| | pipeline_tag: text-generation |
| | library_name: transformers |
| | --- |
| | |
| | # ✨ Klear-Reasoner-8B |
| | We present Klear-Reasoner, a model with long reasoning capabilities that demonstrates careful deliberation during problem solving, achieving outstanding performance across multiple benchmarks. We investigate two key issues with current clipping mechanisms in RL: Clipping suppresses critical exploration signals and ignores suboptimal trajectories. To address these challenges, we propose **G**radient-**P**reserving clipping **P**olicy **O**ptimization (**GPPO**) that gently backpropagates gradients from clipped tokens. |
| |
|
| | | Resource | Link | |
| | |---|---| |
| | | 📝 Preprints | [Paper](https://arxiv.org/pdf/2508.07629) | |
| | | 🤗 Daily Paper | [Paper](https://huggingface.co/papers/2508.07629) | |
| | | 🌐 Project Page | [Klear-Reasoner Website](https://suu990901.github.io/KlearReasoner/) | |
| | | 💻 Code Repo | [Klear-Reasoner GitHub](https://github.com/suu990901/Klear_Reasoner) | |
| | | 🤗 Model Hub | [Klear-Reasoner-8B](https://huggingface.co/Suu/Klear-Reasoner-8B) | |
| | | 🤗 Dataset Hub | [Math RL](https://huggingface.co/datasets/Suu/KlearReasoner-MathSub-30K) | |
| | | 🤗 Dataset Hub | [Code RL](https://huggingface.co/datasets/Suu/KlearReasoner-CodeSub-15K) | |
| | | 🐛 Issues & Discussions | [GitHub Issues](https://github.com/suu990901/Klear_Reasoner/issues) | |
| | | 📧 Contact | suzhenpeng13@163.com | |
| |
|
| | ## 📌 Overview |
| |
|
| | <div align="center"> |
| | <img src="main_result.png" width="100%"/> |
| |
|
| | <sub>Benchmark accuracy of Klear-Reasoner-8B on AIME 2024/2025 (avg@64), LiveCodeBench V5 (2024/08/01-2025/02/01, avg@8), and v6 (2025/02/01-2025/05/01, avg@8).</sub> |
| | </div> |
| |
|
| | Klear-Reasoner is an 8-billion-parameter reasoning model that achieves **SOTA** performance on challenging **math and coding benchmarks**: |
| |
|
| | | Benchmark | AIME 2024 | AIME 2025 | LiveCodeBench V5 | LiveCodeBench V6 | |
| | |---|---|---|---|---| |
| | | **Score** | **90.5 %** | **83.2 %** | **66.0 %** | **58.1 %** | |
| |
|
| | The model combines: |
| | 1. **Quality-centric long CoT SFT** – distilled from DeepSeek-R1-0528. |
| | 2. **Gradient-Preserving Clipping Policy Optimization (GPPO)** – a novel RL method that **keeps gradients from clipped tokens** to boost exploration & convergence. |
| |
|
| | --- |
| |
|
| | ## 📐 GPPO (Gradient-Preserving Clipping Policy Optimization) |
| |
|
| | GPPO is a **plug-and-play** replacement for PPO/GRPO that keeps the clipped tokens **in the computational graph** and lets their gradients flow in a **bounded, controlled** way. |
| |
|
| |
|
| | ### Problem with Vanilla Clipping |
| | Classic importance-ratio clipping (PPO/GRPO) drops all tokens whose ratio |
| | $r_t^{(j)}=\pi_\theta/\pi_{\text{old}}$ falls outside $[1-\varepsilon_l,\ 1+\varepsilon_h]$. |
| | Two side-effects appear: |
| | |
| | - **High-entropy exploratory tokens** (large $r$, positive advantage) are killed → less exploration. |
| | - **Negative trajectories** (small $r$, negative advantage) are ignored → slower correction. |
| | |
| | |
| | ### GPPO Surrogate Loss (Token-Level GRPO) |
| | |
| | Let |
| | - $\delta = r_t^{(j)}(\theta)=\pi_\theta/\pi_{\text{old}}$ (importance ratio) |
| | - $\tilde A^{(j)}$ = group-relative advantage |
| | - $\text{sg}(\cdot)$ = stop-gradient (detach from back-prop) |
| |
|
| | The **GPPO objective** is |
| |
|
| |
|
| |  |
| |
|
| |
|
| | - **Forward**: behaves exactly like Clip-Higher. |
| | - **Backward**: the fraction $\frac{1\pm\varepsilon}{\text{sg}(\delta)}$ keeps the clipped magnitude **but still propagates** a mild gradient. |
| |
|
| |
|
| | ### Gradient Expression |
| |
|
| | Let $\phi_\theta(a_{j,t},s_{j,t})$ be the policy-gradient vector. |
| | The **per-token gradient** is |
| | |
| |  |
| | |
| | |
| | where |
| | |
| |  |
| | |
| | - **Never zero** → every token contributes to learning. |
| | |
| | |
| | ### General Form with Tunable Scaling ($\beta_1$, $\beta_2$) |
| | |
| | For finer-grained control: |
| | |
| |  |
| | |
| | Empirically we set $\beta_1 = \beta_2 = 1$. |
| | |
| | ### Experiment |
| | <div align="center"> |
| | <img src="GPPO.png" width="100%"/> |
| | |
| | <sub>Comparison of GPPO, GRPO w/ Clip Higher, and CISPO in mathematical RL training. Both methods are trained from an earlier long-CoT SFT checkpoint with a sequence length of 32K tokens. For GRPO, we use the Clip-Higher strategy from DAPO with the recommended $$\epsilon_h = 0.28$$.</sub> |
| | </div> |
| |
|
| | --- |
| |
|
| | ### Evaluation |
| | When we expand the inference budget to 64K and adopt the YaRN method with a scaling factor of 2.5. **Evaluation is coming soon, stay tuned.** |
| |
|
| | ## 📊 Benchmark Results (Pass@1) |
| |
|
| | | Model | AIME2024<br>avg@64 | AIME2025<br>avg@64 | HMMT2025<br>avg@64 | LCB V5<br>avg@8 | LCB V6<br>avg@8 | |
| | |-------|--------------------|--------------------|--------------------|-----------------|-----------------| |
| | | AReal-boba-RL-7B | 61.9 | 48.3 | 29.4 | 34.3 | 31.0† | |
| | | MiMo-7B-RL | 68.2 | 55.4 | 35.7 | 57.8 | 49.3 | |
| | | Skywork-OR1-7B | 70.2 | 54.6 | 35.7 | 47.6 | 42.7 | |
| | | AceReason-Nemotron-1.1-7B | 72.6 | 64.8 | 42.9 | 57.2 | 52.1 | |
| | | POLARIS-4B-Preview | 81.2 | _79.4_ | 58.7 | 58.5† | 53.0† | |
| | | Qwen3-8B | 76.0 | 67.3 | 44.7† | 57.5 | 48.4† | |
| | | Deepseek-R1-0528-Distill-8B | _86.0_ | 76.3 | 61.5 | 61.0† | 51.6† | |
| | | OpenReasoning-Nemotron-7B | 84.7 | 78.2 | 63.5 | _65.6_† | _56.3_† | |
| | | Klear-Reasoner-8B-SFT | 75.6 | 70.1 | 57.6 | 58.5 | 49.6 | |
| | | Klear-Reasoner-8B | 83.2 | 75.6 | 60.3 | 61.6 | 53.1 | |
| | | *w/ 64K Inference Budget* | **90.5** | **83.2** | **70.8** | **66.0** | **58.1** | |
| |
|
| | > We report the average `pass@1` results (avg@_n_), with all other evaluation metrics following the DeepSeek-R1 assessment framework (temperature=0.6, top_p=0.95). |
| | |
| | --- |
| | |
| | ## Usage |
| | You can load the model and perform inference using the Hugging Face `transformers` library: |
| | |
| | ```python |
| | from transformers import AutoTokenizer, AutoModelForCausalLM |
| | import torch |
| | |
| | model_name = "Suu/Klear-Reasoner-8B" # or "Suu/Klear-Reasoner-8B-SFT" |
| | tokenizer = AutoTokenizer.from_pretrained(model_name) |
| | model = AutoModelForCausalLM.from_pretrained( |
| | model_name, |
| | torch_dtype=torch.bfloat16, |
| | device_map="auto" |
| | ) |
| | |
| | prompt = "Prove that for all positive integers n, n^3 + 2n is divisible by 3." |
| | messages = [{"role": "user", "content": prompt}] |
| | inputs = tokenizer.apply_chat_template(messages, return_tensors="pt").to(model.device) |
| | |
| | outputs = model.generate( |
| | inputs, |
| | max_new_tokens=8192, |
| | temperature=0.6, |
| | top_p=0.95, |
| | do_sample=True |
| | ) |
| | print(tokenizer.decode(outputs[0], skip_special_tokens=True)) |
| | ``` |
| | |
| | --- |
| |
|
| | ## 🧪 Training |
| | ### Configure the experimental environment |
| | ```bash |
| | git clone https://github.com/suu990901/Klear_Reasoner |
| | cd Klear_Reasoner |
| | pip install -r requirements.txt |
| | ``` |
| | For the code, we use [Firejail](https://github.com/netblue30/firejail) for the **sandbox** environment. Additionally, we implemented multi-process control based on [Pebble](https://github.com/noxdafox/pebble), enabling automatic resource reclamation upon task timeout. For mathematics, we use [math_verify](https://github.com/huggingface/Math-Verify) for judging. |
| |
|
| | ### Training Data Format |
| | Please refer to the format of the two provided datasets, [Math RL](https://huggingface.co/datasets/Suu/KlearReasoner-MathSub-30K) and [Code RL](https://huggingface.co/datasets/Suu/KlearReasoner-CodeSub-15K), for the training data. The format for a single math entry is as follows: |
| | ```json |
| | {"data_source": "math_longcot_math_verify", "prompt": [{"content": "Let $n=9867$. If you calculated $n^{3}-n^{2}$, what would be the unit digit found?\ |
| | (a) 0\ |
| | (b) 2\ |
| | (c) 4\ |
| | (d) 6\ |
| | (e) 8", "role": "user"}], "ability": "math", "reward_model": {"ground_truth": "4", "style": "rule"}, "__index_level_0__": "29999"} |
| | ``` |
| | |
| | Here, the data_source field is set to "math_longcot_math_verify". |
| |
|
| | The format for a single code entry is as follows: |
| | ```json |
| | {"hash": "47c43857280be8a7557cc36b998b3012", "ability": "code", "data_source": "coder1_longcot", "prompt": [{"content": "You are an expert Python programmer. You will be given a question (problem specification) and will generate a correct Python program that matches the specification and passes all tests.\ |
| | \ |
| | Takahashi is planning to eat N dishes.\ |
| | The i-th dish he plans to eat is sweet if S_i = sweet, and salty if S_i = salty.\ |
| | If he eats two sweet dishes consecutively, he will feel sick and be unable to eat any more dishes.\ |
| | Determine whether he can eat all the dishes...", "role": "user"}], "reward_model": {"ground_truth": "...", "style": "rule"}} |
| | ``` |
| |
|
| | Here, the data_source field is set to "coder1_longcot". |
| |
|
| | **The data_source field affects the choice of verifier.** |
| | |
| | ### Using Ray for Multi-Node Training |
| | For multi-node training, ensure all nodes are started and connected via Ray before executing the training script. Below is a brief setup guide for Ray across multiple machines: |
| | #### Step 1: Start Ray on the Head Node (node0) |
| | |
| | On the first node (typically called `node0`), run: |
| | |
| | ```bash |
| | ray start --head --dashboard-host=0.0.0.0 |
| | ``` |
| | |
| | Get the IP address of the master node. |
| | ```bash |
| | MASTER_IP=$(hostname -I | awk '{print $1}') |
| | ``` |
| | #### Step 2: Connect Other Nodes (e.g., node1) |
| | |
| | On each additional worker node (e.g., `node1`), run the following, replacing the IP with that of your head node: |
| | |
| | ```bash |
| | ray start --address=\"$MASTER_IP:6379\" |
| | ``` |
| | |
| | ### RL Training |
| | Run the following script on the master node to start the training task. |
| | |
| | ```bash |
| | bash recipe/dapo/perf_run_dapo_ours_math.sh # For Math RL |
| | bash recipe/dapo/perf_run_dapo_ours_code.sh # For Code RL |
| | ``` |
| | |
| | In the startup script, you need to set the following variables: |
| | ```bash |
| | YOUR_MODEL_PATH="<your_model_path>" |
| | CKPTS_SAVE_DIR="<ckpts_save_path>" |
| | YOUR_TRAIN_FILE="<train_data_path>" |
| | YOUR_TEST_FILE="<test_data_path>" |
| | ``` |
| | |
| | --- |
| | ## 🤝 Citation |
| | If you find this work helpful, please cite our paper: |
| | ```bibtex |
| | @misc{su2025klearreasoneradvancingreasoningcapability, |
| | title={Klear-Reasoner: Advancing Reasoning Capability via Gradient-Preserving Clipping Policy Optimization}, |
| | author={Zhenpeng Su and Leiyu Pan and Xue Bai and Dening Liu and Guanting Dong and Jiaming Huang and Wenping Hu and Guorui Zhou}, |
| | year={2025}, |
| | eprint={2508.07629}, |
| | archivePrefix={arXiv}, |
| | primaryClass={cs.LG}, |
| | url={https://arxiv.org/abs/2508.07629}, |
| | } |
| | ``` |