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OPcache is PHP’s built-in bytecode cache. It stores compiled PHP scripts in memory so the server doesn’t recompile every file on every request. It’s one of the highest-impact performance settings available: commonly up to 3x faster PHP execution: and it’s standard on properly configured production WordPress hosts.
| Alert | Meaning |
|---|---|
| OPcache Disabled (warning) | The extension is installed but not active |
| OPcache Missing (warning) | The extension isn’t installed at all |
| Without OPcache | With OPcache |
|---|---|
| Every PHP file recompiled per request | Compiled bytecode reused from memory |
| High CPU usage, slow execution | Fast execution, low CPU usage |
| Wasted server capacity | Headroom for real traffic |
opcache there (Xponent does this for you).zend_extension=opcache.so
opcache.enable=1
opcache.memory_consumption=128
opcache.interned_strings_buffer=16
opcache.max_accelerated_files=10000
opcache.revalidate_freq=2
opcache.validate_timestamps=1
A healthy OPcache shows a hit rate of 95%+. Lower hit rates usually mean:
| Hit rate | Likely cause |
|---|---|
| < 90% | Memory too small (opcache.memory_consumption), or revalidation too aggressive |
| 80-90% | Many files, cache thrashing: raise memory and max_accelerated_files |
| Very low | opcache.validate_timestamps + revalidate_freq=0 forcing recompiles |
You can see hit rate via a phpinfo() page (OPcache section) or WP-CLI (wp eval 'opcache_get_status()').
With validate_timestamps=1 and a short revalidate_freq, PHP checks file mtimes: changes appear within seconds. If a host disables timestamp validation for performance, new code won’t appear until OPcache is flushed (which is why some hosts purge cache after deploys). Xponent tunes this so your updates appear immediately while keeping the cache effective.
Nothing. If your host doesn’t support installing PHP extensions, that’s a strong signal it’s time to migrate to Xponent, where the full performance stack is managed.
