# How to read your cache diagnostics > Check the plumbing caching depends on — PHP version, the drop-in, the WP_CACHE constant, directory permissions — and get the server snippet your setup is missing. - Category: Health & insights - Canonical: https://xspeedcache.com/docs/cache-diagnostics/ --- Caching depends on several things being true at once: a modern PHP, a writable directory, a drop-in in the right place, a constant defined in `wp-config.php`. If any one is missing, caching quietly does less than you think. The **Overview** tab checks each and tells you which is wrong. > **Where to find it** > > 1. In your WordPress admin, click **xSpeed Cache** in the left menu. > 2. In the xSpeed Cache sidebar, open the **Health & insights** group. > 3. Click the **Health** card — **Overview** is the default tab. > > *Shortcut: open `wp-admin/admin.php?page=xspeed#/insights/health` directly.* > > ✅ This tab is part of **xSpeed Cache (Free)**. ![The 24-hour hit ratio](https://xspeedcache.com/_astro/health-hitratio.Biw7-0o6.png) 1. **Hit ratio · 24h** — with a sparkline of recent history. > 💡 **This counts requests that reached your server.** If a CDN or [Cloudflare](https://xspeedcache.com/docs/cloudflare/) sits in front, edge-served requests never arrive here and aren't counted — which is why this figure can differ from your analytics, and why it is described as origin-layer only. --- ## Settings at a glance This tab has no settings — it's a read-only diagnostic report: | Element | What it shows | | --- | --- | | **Hit ratio · 24h** | Percentage served from cache, with hit and miss counts. | | **Diagnostics list** | Pass/warn status for each caching prerequisite. | | **Recommendations** | ⭐ Pro — ranked, rule-based suggestions with an **Apply** button. | | **Server config snippet** | The nginx or Apache config your setup needs. | --- ## How it works Every item is checked live when the panel loads — nothing here is cached or remembered from a previous visit. A coloured dot marks each: green for satisfied, amber for something needing attention, grey for informational. The hit ratio at the top is drawn from the same 24-hour counters that [Page Cache](https://xspeedcache.com/docs/page-cache/) reports and [Adaptive Cache](https://xspeedcache.com/docs/adaptive-cache/) profiles, so all three agree. --- ## Recommendations ![The recommendations list](https://xspeedcache.com/_astro/health-recommendations.DFQjagUA.png) 1. **Suggestion count** — with **Re-scan** to re-evaluate. 2. **Individual suggestions** — each with a severity and an action. > ⭐ **Recommendations is part of xSpeed Pro.** Without a licence this card shows a locked preview; everything else on this tab is Free. A rule-based engine audits your current settings plus your server state and surfaces the changes most likely to improve things. Each carries a severity — **Medium**, **Low** — and most have an **Apply** button that makes the change for you. Some are marked **Manual** instead. Those need something xSpeed can't do from WordPress — installing Redis, for instance, is a server task, so the panel explains it rather than offering a button. This is the most useful thing on the tab for most people. Rather than reading every panel and deciding what matters, you get a short ranked list derived from your actual configuration. > 💡 **Re-scan after making changes.** The suggestions reflect state at scan time, so a recommendation you've already acted on will linger until you re-scan. > 💡 **It only appears on this tab.** The summary bar above the tab strip follows you to [Visitors](https://xspeedcache.com/docs/visitors/) and [PageSpeed](https://xspeedcache.com/docs/pagespeed/); the recommendations do not — switch tabs and they're gone until you come back here. --- ## The diagnostics list ![The diagnostics checks](https://xspeedcache.com/_astro/health-diagnostics.Bsx_UcxI.png) 1. **Diagnostics** — each prerequisite with its current status. | Check | What it means | | --- | --- | | **WordPress version** | Meets the 6.0+ minimum xSpeed requires. | | **PHP version** | Modern PHP runs meaningfully faster. | | **Server** | Which server was detected — this determines what xSpeed can configure automatically. | | **Cache directory writable** | Without write access, nothing can be cached at all. | | **advanced-cache.php drop-in** | The file that serves cached pages before WordPress loads. | | **WP_CACHE constant** | Must be defined and truthy in `wp-config.php`, or the drop-in is never used. | | **Static-file rewrite** | Whether your server routes directly to cached files, skipping PHP. | The last three are the ones worth understanding, because they form a chain. **The drop-in and the constant work as a pair.** `advanced-cache.php` is what serves a cached page before WordPress fully loads — but WordPress only looks for it when `WP_CACHE` is `true`. Either one missing and page caching silently doesn't happen, even with everything switched on in the settings. **Static-file rewrite is the optional last step.** By default the drop-in serves cached HTML through PHP, which is already fast. With a server rewrite, your server finds the cached file itself and never invokes PHP — faster still. On nginx that requires pasting config manually, so this check often shows amber even on a correctly configured site. Amber here means "there's more available", not "something is broken". --- ## The server config snippet ![The nginx configuration snippet](https://xspeedcache.com/_astro/health-nginx.BB0sUEhG.png) 1. **Server config** — the unified snippet for your server, with **Copy**. When your server needs manual configuration, the full snippet appears here with a copy button. It's *unified* — one block covering static-file rewrites, compression directives, and cache headers together, rather than separate snippets per feature. That matters for a practical reason. Several panels ([GZIP](https://xspeedcache.com/docs/gzip/), [Browser Cache](https://xspeedcache.com/docs/browser-cache/), Page Cache) each need nginx directives, and this is where they're gathered. You paste once rather than hunting through panels. > ⚠️ **Re-copy the snippet after toggling features.** The block is generated from your current settings, so enabling something that needs a directive changes it. The panel says as much — re-copy after toggling features, and reload nginx afterwards. --- ## Related - [How to check your site health](https://xspeedcache.com/docs/health/) - [How to measure real visitor speed](https://xspeedcache.com/docs/visitors/) - [How to run a PageSpeed audit](https://xspeedcache.com/docs/pagespeed/) - [How to enable Page Cache](https://xspeedcache.com/docs/page-cache/) - [How to read the activity log](https://xspeedcache.com/docs/logs/)