How to install the APCu PHP module on a Plesk server?

Warning: APCu is not officially supported by Plesk and was not tested extensively. Use the instructions below at your own risk.

1. Connect to the server via SSH.

2. Install required development packages:

   • For .deb-based OS (Ubuntu, Debian):

     # apt install plesk-php80-dev zlib1g-dev gcc make

   • For .rpm-based OS (CentOS, RHEL, CloudLinux):

     # yum install plesk-php80-devel zlib-devel gcc make

   Note: As an example, Plesk PHP 7.0 development package is installed. For a different version of PHP change php80 to the required version, for instance, php70, php56

3. Install the APCu PHP module:

   • For Plesk PHP 5.x:

     # /opt/plesk/php/5.x/bin/pecl install apcu-4.0.11

   • For Plesk PHP 7.x::

     # /opt/plesk/php/7.x/bin/pecl install apcu

1. • For Plesk PHP 8.x
     # /opt/plesk/php/8.x/bin/pecl install apcu
     
     

2. Enable APCu in PHP configuration:

   # echo "extension=apcu.so" > /opt/plesk/php/8.0/etc/php.d/apcu.ini
   
   

3. Restart PHP service and refresh PHP handlers information:

   # service plesk-php80-fpm restart

   # plesk bin php_handler --reread

4. Verify that the module is loaded and is working:

   # /opt/plesk/php/8.0/bin/php -i | grep apc.enabled
   apc.enabled => On => On
   
   

   To check whether APCu is enabled, open the php_info() page and find the following content: