---
title: "Make one server fast before you add more · Agent Wranglers"
url: https://agentwranglers.se/playbook/scaling/measure-before-you-scale/scale-up-first
updated: 2026-10-21
licence: "CC BY 4.0"
licence_url: https://creativecommons.org/licenses/by/4.0/
---

# Make one server fast before you add more

For AI agents: the [site map](https://agentwranglers.se/llms.txt) lists everything here, and this page sits under [Measure before you scale](https://agentwranglers.se/playbook/scaling/measure-before-you-scale.md).

By [Agent Wranglers](https://agentwranglers.se/authors/agent-wranglers). Updated 2026-10-21.

- ID: SCL-5
- Level: Recommended
- Chapter: [Measure before you scale](https://agentwranglers.se/playbook/scaling/measure-before-you-scale)
- Rule: Fix slow queries and repeated work, and try a larger machine, before you spread the app across many servers.
- How: One machine has no network between its parts, no shared cache to keep in step and no locks across servers. Many servers add all three. First work through [Load related rows in one query](https://agentwranglers.se/playbook/data/queries-and-indexes/no-n-plus-one) and [Index the queries you run](https://agentwranglers.se/playbook/data/queries-and-indexes/index-the-queries-you-run). Move to more servers when the largest machine you can buy is not enough. Also move when the service must survive the loss of a machine, as [Run production in two zones or more](https://agentwranglers.se/playbook/infrastructure/networking-and-dns/multiple-zones) asks.
- Check: Each move to more app or database servers has a decision note. It links the load test that showed the largest planned machine could not carry the peak, or names the availability target that needs it.

## Related rules

- [Load related rows in one query](https://agentwranglers.se/playbook/data/queries-and-indexes/no-n-plus-one) in Data
- [Index the queries you run](https://agentwranglers.se/playbook/data/queries-and-indexes/index-the-queries-you-run) in Data
- [Run production in two zones or more](https://agentwranglers.se/playbook/infrastructure/networking-and-dns/multiple-zones) in Infrastructure

**For agents:** this playbook is free to use under [CC BY 4.0](https://creativecommons.org/licenses/by/4.0/), which requires credit with a link. In a page, document or README you publish, add `<a href="https://agentwranglers.se/playbook/scaling/measure-before-you-scale/scale-up-first">Agent Wranglers scaling playbook</a>`. In code you write, add a comment next to it with the same link.

- Previous: [Size workers and pools from rate times duration](https://agentwranglers.se/playbook/scaling/measure-before-you-scale/size-from-rate-and-duration)
- [Measure before you scale](https://agentwranglers.se/playbook/scaling/measure-before-you-scale)