Aero Cache Warmer: Automatic Warming, llms.txt, and Priority Edge

A cold cache is a trap. You purge (correctly) after a content change, and the very next visitor, maybe a real person, maybe Googlebot, pays the full render cost while the cache rebuilds around them. The Cache Warmer (Aero → Cache Warmer) exists to close that gap: it proactively re-requests your pages right after a flush, so Batcache and Edge Cache are already warm before real traffic arrives.

Warmer settings

Enable Cache Warmer: Safe, recommended

Master switch. With this off, nothing warms, manually or automatically, regardless of what else is configured below.

Warm automatically after every flush: Safe, recommended

The moment any full flush completes (manual, admin bar, automated trigger, or scheduled), the warmer rebuilds cache before real visitors arrive. This is the setting that actually delivers on the promise above; without it, warming only happens when you remember to trigger it by hand.

Also warm the Guest (bot) cache bucket: Situational, only relevant with Guest Mode

When Guest Mode cache isolation is active (see the Experimental page), each URL gets warmed twice: once as a regular visitor, once as a PageSpeed-style bot, so both buckets stay hot. This doubles request volume during warming. It’s inert and grayed out if Guest Mode isolation is off.

Include URLs from llms.txt: Safe if you maintain an llms.txt file

If a file exists at /llms.txt, the warmer treats it as a curated list of your most important pages and warms those ahead of the general sitemap crawl. Read the callout below before you file this under “SEO,” because Google specifically says it doesn’t count as one.

Priority Edge, keeping top URLs admitted at the Edge: Safe, recommended

Runs a lightweight pass every 10 minutes against the URLs in your Priority Edge list (below), keeping them continuously admitted at the fastest cache tier. With just a homepage in the list, that’s three tiny requests every ten minutes, negligible load for guaranteed fast serving on the pages that matter most.

Aero’s llms.txt support is a warming convenience, not an SEO or AI-visibility feature for Google. Google has stated directly that it doesn’t use llms.txt or any similar machine-readable file for Search or its generative AI features (that said, ChatGPT, Claude, and Perplexity may use llms.txt), and that creating one “will neither harm nor help your site’s visibility or rankings in Google Search.” (Source: Google’s generative AI search guide, under “Mythbusting generative AI search.”) If you already maintain an llms.txt for other AI tools or agents that do read it, this setting is a nice bonus: those same important pages get warmed first. Don’t create one purely on the assumption it moves the needle in Google Search, because it doesn’t.

Warming behavior

Field	Options	Guidance
URLs per warm run	10 / 25 / 50 / 100 / 250 / 500 / all detectable	Homepage and priority URLs always warm first, then llms.txt, then the sitemap fills the rest. Start around 50 to 100 for most sites. “All detectable” is capped at 5,000 URLs for safety, but on a large site a full run takes a while and generates real load, schedule it off-peak if you use it.
Requests per batch	2 (gentle) / 5 (balanced) / 8 (aggressive)	Batches run roughly 15 seconds apart via WP-Cron. Lower is kinder to resource-constrained hosting; only go aggressive if you’ve confirmed your server handles it without slowing down live traffic.
Sitemap URL	auto-detect by default	Leave empty unless you have a nonstandard sitemap location. Yoast, RankMath, and core sitemap indexes are followed automatically, including nested sitemap-of-sitemaps structures.
Priority URLs	one per line	Warmed first, every run, regardless of the limit above. Good candidates: pricing, contact, and any landing page you’re actively driving paid or campaign traffic to.
Exclude from warming	one per line, case-insensitive fragment match	Add anything dynamic that never benefits from caching: `/cart/`, `/my-account/`, search results pages, and similar. Warming these wastes requests on pages that shouldn’t be cached in the first place.

Priority Edge

A short list (up to 10 URLs) that gets kept continuously admitted at WP Stratos’s Edge Cache tier, the fastest possible serve, regardless of normal traffic patterns. Edge admission normally requires two visits within two minutes; Priority Edge sidesteps that by generating the qualifying hits itself on a 10-minute cycle, then verifies admission actually took by checking the response’s x-ac header. Use this for your handful of highest-value pages: homepage, primary conversion page, anything you’d be embarrassed to have serve slowly during a spike in interest. General warming and the URL limit setting handle the rest of the site.

Scheduled warming

A belt-and-suspenders setting independent of the after-flush warming above: runs a full warm pass on an interval (hourly through weekly), so pages whose Batcache TTL naturally expired get rebuilt before a visitor notices the gap. This runs on its own schedule, separate from the flush schedule on Purge & Schedule, but the two are worth coordinating: pair the interval here with your Batcache max_age, if pages are cached for 24 hours, a daily scheduled warm keeps things from ever going fully cold between expirations.

Why this matters beyond “faster pages”

A warm cache isn’t only a visitor-experience metric. Crawlers, including Googlebot, are sensitive to response time and server load when deciding how much of a site to crawl in a given window, a concept Google calls crawl budget and covers in its crawl budget guidance. A site that’s consistently fast to respond, because pages are warm rather than regenerating on demand, is a site that’s easier and cheaper for a crawler to work through. That’s a quiet, compounding advantage that has nothing to do with keyword density and everything to do with technical reliability.

WP Postman

Aero

WP Stratos Environment

Aero Cache Warmer: Automatic Warming, llms.txt, and Priority Edge

Warmer settings

Warming behavior

Priority Edge

Scheduled warming

Why this matters beyond “faster pages”

​Warmer settings

​Warming behavior

​Priority Edge

​Scheduled warming

​Why this matters beyond “faster pages”

Warmer settings

Warming behavior

Priority Edge

Scheduled warming

Why this matters beyond “faster pages”