---
license: apache-2.0
base_model: Qwen/Qwen3-1.7B-Base
tags: [reinforcement-learning, grpo, code-generation, mbpp, catastrophic-forgetting]
---

# code-q3_1p7b-nobuf

GRPO on MBPP from `Qwen/Qwen3-1.7B-Base`. Arm: **GRPO, no replay buffer**.

Part of a study of forgetting during code RL: the same run is trained with and
without an SFT-replay buffer, and evaluated on MBPP+ across training.

## Layout

One subfolder per checkpoint, `global_step_<N>/`, each a full Hugging Face model
directory. Steps are the stride-30 evaluation grid plus the run's endpoint
(30, 60, 90, 120, 150, 180, 210, 240, 270, 300, 330, 360, 390, 420, 450, 480, 510, 540, 570, 600, 630, 660, 690, 720, 750, 780, 800).

```python
from transformers import AutoModelForCausalLM, AutoTokenizer
m = AutoModelForCausalLM.from_pretrained("RL-Forgetting-Experiments-3/code-q3_1p7b-nobuf", subfolder="global_step_800")
t = AutoTokenizer.from_pretrained("RL-Forgetting-Experiments-3/code-q3_1p7b-nobuf", subfolder="global_step_800")
```

## Training

- Data: 320 MBPP problems, held out from both MBPP+ (378) and MBPP's canonical
  test split (276), so both remain reportable.
- GRPO, 8 rollouts per prompt, batch 64, actor lr 1e-6, response length 3072.
- Reward: execution of the generated program against the task's asserts (binary).
- Buffer arms replay 128 past rollouts per step with weight lambda=0.1, sampled
  by `hard_cooldown`.

## Evaluation

MBPP+ (378 problems), n=160 samples, temperature 0.6, top_p 0.95, unbiased
pass@k. Note that scoring against MBPP+'s full test suite is substantially
stricter than MBPP's original 3 asserts (~8-10 points of pass@1).