---
license: cc-by-4.0
pretty_name: A Year in LLM Serving — Chutes Production Trace
size_categories:
- 1B<n<10B
tags:
- llm-serving
- inference
- workload-trace
- prefix-caching
- load-balancing
configs:
- config_name: trace
  default: true
  data_files:
  - split: train
    path: data/trace/train-*.parquet
- config_name: chute_models
  data_files:
  - split: train
    path: data/chute_models.parquet
---
# A Year in LLM Serving — Chutes Production Trace

This dataset contains one year of production LLM-serving traffic from [Chutes](https://chutes.ai/), with **6,122,413,756 requests** across **9,174 models**. Each row represents one API invocation.

The dataset accompanies the paper *A Year in LLM Serving: Workload Evolution, Caching and Load-Balancing* ([arXiv:2608.13573](https://arxiv.org/abs/2608.13573)).

The trace includes request timing, model and anonymized user identifiers, serving instances, token counts, time-to-first-token (TTFT), and prefix-cache reuse.

## Subsets

| Subset | Rows | Description |
|---|---:|---|
| `trace` (default) | 6,122,413,756 | Request-level trace in 45 Parquet shards (~91 GB), ordered by `started_at` |
| `chute_models` | 4,558 | Model metadata, including model name, invocation count, and supported GPUs |

## Trace Schema

| Field | Type | Description |
|---|---|---|
| `invocation_id` | int64 | Request identifier |
| `function_name` | string | API endpoint |
| `chute_id` | string | Model identifier; join with `chute_models` for model metadata |
| `user_id` | string | Anonymized user identifier |
| `rehash_round` | int32 | User anonymization rotation |
| `instance_id` | string | Serving instance identifier |
| `started_at` | timestamp[us] | Request start time |
| `completed_at` | timestamp[us] | Request completion time |
| `it` | float | Input tokens |
| `ot` | float | Output tokens |
| `ct` | float | Cached prefix tokens |
| `ttft` | float | Time to first token in seconds |

## Notes

- Timestamps are normalized, preserving relative timing but not the original dates.
- User identifiers are re-anonymized every three months. Use `(user_id, rehash_round)` as the user identifier.
- `ct` is available for approximately the last 10 weeks of the trace and is null before then.
- `chute_models` provides model names for 3,922 of the 9,174 `chute_id`s in the trace, covering 93.8% of all requests. The remaining `chute_id`s correspond to private or short-lived models.
## Usage

### DuckDB

Query the Parquet files directly from the Hugging Face Hub:

```sql
SELECT
    chute_id,
    count(*) AS requests,
    approx_quantile(ttft, 0.5) AS p50_ttft
FROM 'hf://datasets/harvardMadsys/chutes_metadata/data/trace/*.parquet'
GROUP BY chute_id
ORDER BY requests DESC
LIMIT 10;
```

### Hugging Face Datasets

```python
from datasets import load_dataset

trace = load_dataset(
    "harvardMadsys/chutes_metadata",
    "trace",
    split="train",
    streaming=True,
)

models = load_dataset(
    "harvardMadsys/chutes_metadata",
    "chute_models",
    split="train",
)
```

### Download

```bash
hf download harvardMadsys/chutes_metadata \
    --repo-type dataset \
    --local-dir chutes_trace
```

## License

This dataset is released under the [Creative Commons Attribution 4.0 International License (CC BY 4.0)](https://creativecommons.org/licenses/by/4.0/).

If you use this dataset, please cite the paper below.

## Citation

```bibtex
@article{nixon2026year,
  title={A Year in LLM Serving: Workload Evolution, Caching and Load-Balancing},
  author={Nixon, William and Durbin, Jon and Standhartinger, Florian and Gunawi, Haryadi S and Yang, Juncheng},
  journal={arXiv preprint arXiv:2608.13573},
  year={2026}
}
```