PHPRay

PHPRay is always-on request tracing for PHP: every request gets a lightweight record of its timing, SQL queries, outbound HTTP calls, PHP errors and N+1 query patterns, at an overhead low enough to leave on in production (see Overhead for what has been measured so far).

On top of the always-on summary, PHPRay runs sampled per-plugin and per-component breakdowns, so you can see which plugin, theme or function eats the request time without profiling every request.

PHPRay works inside PHP itself — there is no root-level agent, sidecar or JVM. It is a PHP extension plus a small on-box collector and a local dashboard, and it runs on shared hosting (CageFS / lsphp), dedicated VPS boxes and containers alike.

The core is free: extension, collector and local dashboard under an open license. The optional PHPRay Cloud fleet console adds cross-server dashboards, plans and alerts, starting at 19 USD per month.

Overhead

The always-on layer hooks request-level events only (request start/end, SQL, outbound HTTP, file I/O, PHP errors) and never sees individual function calls. Per-function profiling uses PHP's observer API and runs only for sampled requests (default 3 %); the other 97 % take no function-level samples at all.

Our internal benchmark (WooCommerce store, 22 plugins, PHP 8.3, OPcache) puts the always-on layer within the measurement noise of the bare-PHP baseline, and profiling of every request measurably above it, yet far below what a classic execute_ex hook costs. Those runs were made on a laptop, so we do not quote them as product figures: certified numbers, the methodology and the raw data will be published once the suite has run on a dedicated, quiet host. Until then treat any precise overhead figure you see quoted for PHPRay as unverified.