# Stale reads

> A Cache served values past their TTL: a write-heavy table outran its invalidation, and reads of the same rows came back old.

## What happens

A Cache served values past their TTL: a write-heavy table outran its invalidation, and reads of the same rows came back old.

## How to prevent it

A shorter TTL, a Cache that writes through, or read-your-writes routing.

The postmortem opens the first of these that you do not own yet:

- [Caching](https://wiki.playquorum.dev/research/caching.md)

## Components it hits

[Cache](https://wiki.playquorum.dev/components/cache.md)

## Facts

SEV2 Stale reads
- **First Era:** [Seed](https://wiki.playquorum.dev/eras/seed.md)
- **Starts at:** SEV2
- **Escalates to:** SEV1
- **Lasts:** 1 min

## See also

- [Incidents](https://wiki.playquorum.dev/incidents.md)

Source: https://wiki.playquorum.dev/incidents/stale-read