Enable PHP OPcache

PHP OPcache stores the compiled bytecode of each PHP file in shared memory, so repeat requests skip parsing and compiling the source. It does not store finished HTML, images or MySQL query results. Those belong to a page cache, a CDN or an object cache such as Redis.

The cache belongs to the PHP workers of one PHP version on the server, not to the visitor’s browser. It is switched on in php.ini with opcache.enable, never through a WordPress plugin, and the PHP manual (read 30 October 2026) gives that switch a default of 1.

• Scope: one cache per PHP version and pool; two sites on PHP 8.2 and 8.3 have separate caches.
• Runtime limit: ini_set('opcache.enable', 1) cannot turn it on. A script can only turn it off, and trying to enable it raises a warning.
• Command line: CLI PHP (wp-cli, artisan, cron scripts) is excluded unless opcache.enable_cli=1, which only the main php.ini can set.

In cPanel the switch lives in MultiPHP INI Editor under Software, set per domain. On WebJi® cPanel hosting you reach the panel from the client area, which is separate from the invoice pages. Changing the PHP version alone does not change opcache.enable.

1. Log in to cPanel and open Software, then MultiPHP INI Editor.
2. Select the domain. If opcache.enable is not in the Basic Mode list, switch to Editor Mode.
3. Set opcache.enable to 1, or add the line opcache.enable=1 if it is absent.
4. Leave opcache.memory_consumption at 128 for now. The manual minimum is 8.
5. Save, reload info.php and confirm On. Delete the file.

If the value stays Off after saving, a php.ini or .user.ini inside the site folder is overriding the editor; the same leftover file often pins an old memory_limit. The cPanel PHP version guide shows where those files hide. WebJi® cPanel accounts list PHP 8.1, 8.2 and 8.3 in MultiPHP Manager; email support@webji.services if an application needs a version outside that list.

For one WordPress or Laravel site the manual defaults are sound; change memory or file limits only when the status numbers show the cache is short. Defaults below are from the PHP manual, read 30 October 2026.

Keep opcache.save_comments=1: at 0 the docblocks disappear and code that reads annotations breaks. Remove any opcache.fast_shutdown line copied from an old tutorial; the directive was dropped in PHP 7.2.

Look at the OOM restarts and Free memory lines in the phpinfo OPcache block: a non-zero OOM count or free memory near zero means the cache is too small. Raise opcache.memory_consumption in steps, for example 128 to 192, and recheck after a day of normal traffic.

If phpinfo is not convenient, a short script prints the same counters, provided opcache.restrict_api does not block it:

<?php
$s = opcache_get_status(false);
echo 'enabled: ', var_export($s['opcache_enabled'], true), "\n";
echo 'free MB: ', round($s['memory_usage']['free_memory'] / 1048576, 1), "\n";
echo 'oom restarts: ', $s['opcache_statistics']['oom_restarts'], "\n";
echo 'cached scripts: ', $s['opcache_statistics']['num_cached_scripts'], "\n";

Expect a shorter PHP processing time, not a universal percentage. A page that waits on a slow MySQL query or a heavy hero image will not feel much faster; speeding up a WordPress website covers the other layers. Several sites on one server each add their own scripts, so a multi-site VPS usually needs more than the 128 MB default.