# The Multivac — Evaluation Report

**Evaluation ID:** EVAL-20260315-034630
**Date:** Mar 15, 2026
**Category:** code
**Question ID:** EVAL-20260315-034630

---

## Question

Your Node.js API is responding with 502 errors under load. Here's the relevant code and infrastructure:

- Express.js API behind an Nginx reverse proxy
- Connection pool to PostgreSQL (max 20 connections)
- Average response time: 50ms normally, 30s+ during incidents
- Error logs show: "connect ETIMEDOUT" and "too many clients already"
- The issue starts when traffic exceeds 200 req/s

```javascript
app.get('/api/users/:id', async (req, res) => {
  const client = await pool.connect();
  const result = await client.query('SELECT * FROM users WHERE id = $1', [req.params.id]);
  res.json(result.rows[0]);
});
```

What's wrong? Provide the fix and explain the connection pool exhaustion pattern.

---

## Winner

**Kimi K2.5** (openrouter)
- Winner Score: 9.57
- Matrix Average: 8.97
- Total Judgments: 83

---

## Rankings

| Rank | Model | Provider | Avg Score | Judgments |
|------|-------|----------|-----------|----------|
| 1 | Kimi K2.5 | openrouter | 9.57 | 9 |
| 2 | Gemma 3 27B | openrouter | 9.47 | 8 |
| 3 | Qwen 3 8B | openrouter | 9.45 | 8 |
| 4 | Phi-4 14B | openrouter | 9.09 | 8 |
| 5 | Mistral Nemo 12B | openrouter | 9.00 | 8 |
| 6 | Granite 4.0 Micro | openrouter | 8.94 | 8 |
| 7 | Devstral Small | openrouter | 8.81 | 8 |
| 8 | Qwen 3 32B | openrouter | 8.78 | 8 |
| 9 | Llama 4 Scout | openrouter | 8.66 | 9 |
| 10 | Llama 3.1 8B | openrouter | 7.93 | 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 | — | 9.6 | 8.4 | 9.6 | 9.1 | 8.8 | 8.3 | 9.6 | 8.0 | 8.4 |
| Kimi K2.5 | · | — | · | · | 5.8 | · | · | · | · | 3.0 |
| Devstral Small | 9.1 | 10.0 | — | 9.8 | 8.6 | 8.8 | 8.6 | 9.6 | 8.8 | 8.6 |
| Gemma 3 27B | 8.7 | 9.8 | 9.4 | — | 9.8 | 9.8 | 9.4 | 9.8 | 9.8 | 9.2 |
| Llama 4 Scout | 9.4 | 9.8 | 8.6 | 9.8 | — | 9.3 | 9.3 | 9.6 | 8.8 | 8.2 |
| Phi-4 14B | 9.8 | 9.8 | 9.3 | 9.8 | 9.0 | — | 9.2 | 10.0 | 9.4 | 8.6 |
| Granite 4.0 | 8.4 | 8.8 | 8.8 | 8.8 | 8.8 | 8.8 | — | 8.8 | 8.8 | 8.4 |
| Qwen 3 8B | 7.8 | 10.0 | 8.8 | 9.6 | 9.4 | 10.0 | 10.0 | — | 9.4 | 9.0 |
| Mistral Nemo | 8.3 | 8.8 | 8.2 | 8.8 | 8.1 | 8.2 | 8.1 | 9.4 | — | 8.1 |
| Llama 3.1 8B | 8.8 | 9.6 | 9.1 | 9.6 | 9.4 | 9.1 | 8.6 | 8.8 | 9.1 | — |

---

## 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-20260315-034630. 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-20260315-034630/results
Full dataset: https://app.themultivac.com/dashboard/export