# Performance Tuning & Benchmarks

## Baseline

With the default setup — rate-limiting and request logging enabled, as in a normal production deployment — a single Sentinel instance handles roughly 2,000 requests/second on critical endpoints like `/v1/challenge` and `/v1/verify`.

## Scaling up

More CPU cores help directly; RAM beyond 16 GB gives diminishing returns. For low-to-moderate traffic, the built-in embedded database and KV store are enough — reach for external backends as traffic grows.

### Redis

An external Redis or Valkey 7+ instance outperforms the built-in embedded store significantly. Enable it with `REDIS_URL` — see [Databases](/docs/sentinel/databases/#enabling-an-external-redisvalkey).

### Network Database

A [network database](/docs/sentinel/databases/) offloads database operations from the embedded default and is required for [Clustering](/docs/sentinel/operations/clustering/).

### ClickHouse

For high-traffic deployments, offload request logs and analytics to [ClickHouse](/docs/sentinel/operations/clickhouse/) 22.6+ (Enterprise) so they don't compete with the main database for write I/O.

### By traffic volume

- **Low to moderate traffic** — the built-in defaults are sufficient.
- **High traffic** — external Redis/Valkey, network database such as PostgreSQL, and ClickHouse all help independently.

## Benchmarks

> **Note:**
>
> These numbers come from a single MacBook Pro M3 Pro instance tested locally with [Bombardier](https://github.com/codesenberg/bombardier) — useful as a relative baseline, not a guarantee for your own infrastructure.

### Methodology

For an accurate benchmark of your own deployment:

- Disable rate limiting and Autopilot.
- Disable request logging — it can reduce throughput by up to 50%.
- Set `FLOOD_RATE_LIMIT` to empty to disable flood protection.

### Results

| Endpoint | Requests/sec | Avg latency | Max latency | Throughput |
|---|---|---|---|---|
| `GET /v1/challenge` | 5,257.57 | 1.90ms | 52.01ms | 5.29MB/s |
| `POST /v1/verify` | 6,321.77 | 1.58ms | 49.77ms | 7.99MB/s |
| `POST /v1/classifier` (10KB text) | 931.68 | 10.73ms | 255.08ms | 6.03MB/s |

## Related

- **[Databases](/docs/sentinel/databases/)** — enabling external backends.
- **[Clustering](/docs/sentinel/operations/clustering/)** — scaling horizontally across multiple instances.
- **[ENV Variables](/docs/sentinel/operations/env-variables/#rate-limiting--proof-of-work)** — `FLOOD_RATE_LIMIT` and proof-of-work tuning variables.