# Automatic cache warmup

The `cache_warmup` module opens public pages in advance so the first visitor
does not wait for expensive cache generation.

The queue is updated after a full cache flush, saving a published document, a
daily task, or a manual rebuild. A full plan includes the home page and all
published documents.

**URLs per run** limits server load. A value of `10–15` suits a typical site:
Scheduler processes another small batch every minute instead of opening the
whole site at once.

After three failures, a URL waits for a new full plan. The history retains its
HTTP status, response time, and error message.

The base URL may be left empty to use the Scheduler request host. Production
sites should set their canonical HTTPS URL. The outbound HTTP client validates
DNS and rejects private or reserved targets.

Automatic processing requires the [Scheduler](scheduler.md). No public CLI is
required.