Troubleshooting

Troubleshooting

Symptom, cause, fix.

"Not measured, cache served it"

Cause: something answered the request before PHP ran. Every profiling request carries a signed cache-busting argument, so this usually means an edge cache or CDN rule ignoring query strings.

Fix: exclude the profiling requests at the edge, or use browser-driven transport, which the plugin falls back to when it detects the server can't fetch its own pages. Cache-served responses are discarded rather than reported as fast pages, so a run with this warning has fewer measurements, not wrong ones.

The analysis can't reach your pages at all

Cause: loopback requests blocked. Common culprits are a security plugin, Basic Auth on a staging site, a WAF, or a host that blocks a server calling its own hostname.

Fix: the plugin detects security plugins blocking loopbacks and names exactly what to whitelist, and the run continues rather than failing. For Basic Auth, a WAF or a CDN, browser-driven transport profiles through your own browser instead. Baseline, spot and ad-hoc runs support it; Plugin Impact Analysis and cache analysis stay loopback-only.

"An analysis is already running" and nothing is running

Cause: a run that died without releasing its claim, usually a PHP timeout or a fatal mid-run. The claim is held for six hours.

Fix: cancel the run from the Overview tab. If there's nothing to cancel, the claim clears itself when it expires.

The Health box says the mu-plugin loader isn't installed

Cause: either wp-content/mu-plugins genuinely isn't writable, or the site defines DISALLOW_FILE_MODS, which forbids plugins from writing files.

Fix: the Health box distinguishes the three cases and says which one applies, including "out of date, it will be refreshed the next time an analysis runs". Only the not-writable case needs a permissions change.

Another plugin owns db.php

Cause: Query Monitor, or another profiler, installed its own drop-in. Ours doesn't overwrite it.

Fix: the plugin says whose drop-in is in place and offers a temporary swap for the duration of a run. Plugin Impact Analysis requires our drop-in, because the database guard that refuses destructive statements during a measurement lives in it.

No function-level breakdown

Cause: the excimer extension isn't installed, or the run predates installing it.

Fix: Server-Capabilities. The panels distinguish an install requirement from a run that simply needs repeating, and the Tools tab writes the commands for your exact server.

No rows-examined data

Cause: MySQL performance_schema is off, or the database user can't read it.

Fix: the Tools tab writes out the one read-only GRANT needed, with your real database user in it. Without it the analysis runs the same and that single finding doesn't appear.

The shop pages profile as empty

Cause: WooCommerce ships with coming-soon mode on, which hides the store from logged-out visitors. Front-end pages are profiled as a logged-out visitor, so the profiler sees what a visitor sees: nothing.

Fix: turn off woocommerce_coming_soon and woocommerce_store_pages_only, or expect empty shop measurements until you launch.

The checkout flow won't complete

Cause: no payment method that can complete without a live gateway redirect, guest checkout disabled in a way the flow can't satisfy, or the run is being blocked before the payment step.

Fix: run wp sspa checkout-flow --dry-run and read the pre-flight, which lists exactly what the run will trigger and what it needs. Blocked or partial management sequences are reported as blocked rather than silently reporting a shorter time.

A measurement seems to have changed my site

It can't, and if you have evidence otherwise that's a bug worth reporting. Suspects are disabled for the analysis's own test requests only, activation and deactivation routines are silenced, and destructive database statements are refused during a measurement. A plugin that reacts to another being excluded is caught, reported as a finding, and measured together with it from the next run on. See Plugin-Impact-Analysis.

Still stuck

Download the privacy-safe Markdown report for the page or run in question and attach it. It strips SQL literals, query values and identifiers. See Contributing-and-Reporting-a-Problem.

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Related: Installation-and-Requirements · Server-Capabilities · How-It-Measures