# The Multivac — Evaluation Report

**Evaluation ID:** EVAL-20260315-053734
**Date:** Mar 15, 2026
**Category:** code
**Question ID:** EVAL-20260315-053734

---

## Question

This distributed lock implementation has a subtle race condition that can cause two processes to hold the lock simultaneously. Find the bug and fix it.

```python
import redis
import time
import uuid

class DistributedLock:
    def __init__(self, redis_client, lock_name, timeout=10):
        self.redis = redis_client
        self.lock_name = f"lock:{lock_name}"
        self.timeout = timeout
        self.token = str(uuid.uuid4())

    def acquire(self):
        while True:
            if self.redis.setnx(self.lock_name, self.token):
                self.redis.expire(self.lock_name, self.timeout)
                return True
            time.sleep(0.1)

    def release(self):
        if self.redis.get(self.lock_name) == self.token:
            self.redis.delete(self.lock_name)
```

Explain why this is dangerous in production and provide a correct implementation.

---

## Winner

**Gemma 3 27B** (openrouter)
- Winner Score: 9.51
- Matrix Average: 8.56
- Total Judgments: 76

---

## Rankings

| Rank | Model | Provider | Avg Score | Judgments |
|------|-------|----------|-----------|----------|
| 1 | Gemma 3 27B | openrouter | 9.51 | 9 |
| 2 | Qwen 3 32B | openrouter | 9.34 | 8 |
| 3 | Qwen 3 8B | openrouter | 9.32 | 8 |
| 4 | Phi-4 14B | openrouter | 9.23 | 8 |
| 5 | Llama 4 Scout | openrouter | 9.07 | 9 |
| 6 | Devstral Small | openrouter | 9.01 | 7 |
| 7 | Granite 4.0 Micro | openrouter | 8.62 | 7 |
| 8 | Kimi K2.5 | openrouter | 7.57 | 2 |
| 9 | Llama 3.1 8B | openrouter | 6.98 | 9 |
| 10 | Mistral Nemo 12B | openrouter | 6.96 | 9 |

---

## 10×10 Judgment Matrix

Rows = Judge, Columns = Respondent. Self-judgments excluded (—).

| Judge ↓ / Resp → | Qwen 3 32B | Kimi K2.5 | Devstral Small | Gemma 3 27B | Llama 4 Scout | Phi-4 14B | Granite 4.0 | Qwen 3 8B | Mistral Nemo | Llama 3.1 8B |
|---|---|---|---|---|---|---|---|---|---|---|
| Qwen 3 32B | — | · | 7.0 | 10.0 | 10.0 | 7.5 | 6.3 | 9.0 | 4.6 | 5.5 |
| Kimi K2.5 | · | — | · | 9.3 | 5.8 | · | · | · | 1.9 | 1.9 |
| Devstral Small | 9.4 | · | — | 9.8 | 10.0 | 10.0 | 8.2 | 9.0 | 7.6 | 7.6 |
| Gemma 3 27B | 9.8 | · | 9.8 | — | 9.8 | 9.8 | 9.6 | 9.8 | 9.2 | 8.4 |
| Llama 4 Scout | 9.8 | · | 9.6 | 9.8 | — | 10.0 | 8.6 | 9.8 | 8.3 | 8.6 |
| Phi-4 14B | 8.8 | 6.8 | 9.8 | 9.8 | 9.8 | — | 9.8 | 10.0 | 8.7 | 8.8 |
| Granite 4.0 | 8.8 | 8.3 | · | 8.6 | 8.8 | 8.8 | — | 8.8 | 8.8 | 8.4 |
| Qwen 3 8B | 10.0 | · | 9.6 | 10.0 | 10.0 | 9.6 | 8.8 | — | 4.4 | 6.0 |
| Mistral Nemo | 8.6 | · | 8.2 | 9.2 | 8.1 | 8.6 | · | 8.6 | — | 7.8 |
| Llama 3.1 8B | 9.6 | · | 9.1 | 9.0 | 9.4 | 9.6 | 9.1 | 9.6 | 9.2 | — |

---

## Methodology

- **10×10 Blind Peer Matrix:** All models answer the same question, then all models judge all responses.
- **5 Criteria:** Correctness, completeness, clarity, depth, usefulness (each scored 1–10).
- **Self-judgments excluded:** Models do not judge their own responses.
- **Weighted Score:** Composite of all 5 criteria.

---

## Citation

The Multivac (2026). Blind Peer Evaluation: EVAL-20260315-053734. app.themultivac.com

## License

Open data. Free to use, share, and build upon. Please cite The Multivac when using this data.

Download raw JSON: https://app.themultivac.com/api/evaluations/EVAL-20260315-053734/results
Full dataset: https://app.themultivac.com/dashboard/export