Wordpress Planning to add Wordpress OpCache Plugin to centmin.sh menu option 22 installs

Centmin Mod 123.09beta01 and newer have a wordpress auto installer and nginx site auto install configuration routine via centmin.sh menu option 22 which also preinstalls some performance and security related Wordpress plugins. You can see an example of such installation at https://servermanager.guide/122/how-to-install-wordpress-on-centmin-mod-lemp-stack-guide/. I plan to update centmin.sh menu option 22 routine to add Wordpress OpCache plugin which will allow you to see Zend Opcache statistics as well configure it to purge Zend Opcache cache on Wordpress updates. So this thread is a discussion for Centmin Mod Wordpress users to see if Wordpress OpCache plugin is something they'd like to see added and for folks to manually test install on their Wordpress sites and see if it works for them.

Centmin Mod Wordpress & PHP Zend Opcache Background

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By default Centmin Mod PHP-FPM installs with Zend Opcache bytecode caching for better performance but instead of the default opcache.revalidate_freq setting of 2 seconds, Centmin Mod defaults to 180 seconds for better performance due to less rechecking for PHP modifications, updates or changes.

The longer the interval set, the better the performance. But this means PHP script modifications and edits do not register and take effect for the duration of that interval or only until you restart PHP-FPM service to flush the cache. Usually, after I update PHP code, I do a PHP-FPM restart which is just habit

SSH command to view Zend Opcache settings which have their custom defaults set in /etc/centminmod/php.d/zendopcache.ini

Code (Text):

php --ri 'Zend Opcache'

Zend OPcache
Opcode Caching => Disabled
Optimization => Disabled
SHM Cache => Enabled
File Cache => Disabled
Startup Failed => Opcode Caching is disabled for CLI

Directive => Local Value => Master Value
opcache.enable => On => On
opcache.use_cwd => On => On
opcache.validate_timestamps => On => On
opcache.validate_permission => Off => Off
opcache.validate_root => Off => Off
opcache.dups_fix => Off => Off
opcache.revalidate_path => Off => Off
opcache.log_verbosity_level => 1 => 1
opcache.memory_consumption => 800 => 800
opcache.interned_strings_buffer => 8 => 8
opcache.max_accelerated_files => 65407 => 65407
opcache.max_wasted_percentage => 5 => 5
opcache.consistency_checks => 0 => 0
opcache.force_restart_timeout => 180 => 180
opcache.revalidate_freq => 180 => 180
opcache.file_update_protection => 2 => 2
opcache.preferred_memory_model => no value => no value
opcache.blacklist_filename => no value => no value
opcache.max_file_size => 0 => 0
opcache.protect_memory => 0 => 0
opcache.save_comments => 1 => 1
opcache.optimization_level => 0x7FFEBFFF => 0x7FFEBFFF
opcache.opt_debug_level => 0 => 0
opcache.enable_file_override => On => On
opcache.enable_cli => Off => Off
opcache.error_log => no value => no value
opcache.restrict_api => no value => no value
opcache.lockfile_path => /tmp => /tmp
opcache.file_cache => no value => no value
opcache.file_cache_only => 0 => 0
opcache.file_cache_consistency_checks => 1 => 1
opcache.huge_code_pages => Off => Off
opcache.preload => no value => no value
opcache.preload_user => no value => no value

SSH command to list all custom PHP .ini settings files

Code (Text):

php --ini
Configuration File (php.ini) Path: /usr/local/lib
Loaded Configuration File:         /usr/local/lib/php.ini
Scan for additional .ini files in: /etc/centminmod/php.d
Additional .ini files parsed:      /etc/centminmod/php.d/a_customphp.ini,
/etc/centminmod/php.d/curlcainfo.ini,
/etc/centminmod/php.d/geoip.ini,
/etc/centminmod/php.d/igbinary.ini,
/etc/centminmod/php.d/mailparse.ini,
/etc/centminmod/php.d/maxminddb.ini,
/etc/centminmod/php.d/mcrypt.ini,
/etc/centminmod/php.d/mysqlnd.ini,
/etc/centminmod/php.d/preload.ini,
/etc/centminmod/php.d/redis.ini,
/etc/centminmod/php.d/timezonedb.ini,
/etc/centminmod/php.d/zendopcache.ini,
/etc/centminmod/php.d/zz-zendopcache.ini,

Contents of /etc/centminmod/php.d/zendopcache.ini

Code (Text):

zend_extension=opcache.so
;opcache.error_log=/var/log/php_opcache_error.log
opcache.enable=1
opcache.memory_consumption=80
opcache.interned_strings_buffer=8
opcache.max_wasted_percentage=5
opcache.max_accelerated_files=65407
; http://php.net/manual/en/opcache.configuration.php#ini.opcache.revalidate-freq
; defaults to zend opcache checking every 180 seconds for PHP file changes
; set to zero to check every second if you are doing alot of frequent
; php file edits/developer work
; opcache.revalidate_freq=0
opcache.revalidate_freq=180
opcache.fast_shutdown=0
opcache.enable_cli=0
opcache.save_comments=1
opcache.enable_file_override=1
opcache.validate_timestamps=1
opcache.huge_code_pages=0

To perserve and override Zend Opcache settings I created an alphanumeric file that comes after the default file name at /etc/centminmod/php.d/zz-zendopcache.ini which has contents of

Code (Text):

opcache.memory_consumption=800
opcache.interned_strings_buffer=8
opcache.max_wasted_percentage=5
opcache.max_accelerated_files=65407
; http://php.net/manual/en/opcache.configuration.php#ini.opcache.revalidate-freq
; defaults to zend opcache checking every 180 seconds for PHP file changes
; set to zero to check every second if you are doing alot of frequent
; php file edits/developer work
; opcache.revalidate_freq=0
opcache.revalidate_freq=180
opcache.fast_shutdown=0
opcache.enable_cli=0
opcache.save_comments=1
opcache.enable_file_override=1
opcache.validate_timestamps=1
;opcache.huge_code_pages=1

Wordpress OpCache Plugin Install

To test Wordpress Opcache plugin you can manually install it on your server either via Wordpress Admin add new plugin section. Or via below SSH commands - yes no need for FTP or Wordpress Admin GUI really

To install via SSH command line, run below commands replacing yourdomain.com in vhostname variable with your actual Wordpress Nginx site domain corresponding with your Wordpress install directory path i.e. if you installed Wordpress at yourdomain.com, then web install path would be /home/nginx/domains/yourdomain.com/public.

Code (Text):

vhostname=yourdomain.com
cd /home/nginx/domains/${vhostname}/public
wp plugin install flush-opcache --activate --allow-root
wp option update flush-opcache-upgrade 1 --allow-root
chown -R nginx:nginx /home/nginx/domains/${vhostname}/public/wp-content/plugins/
nprestart
wp plugin list --allow-root

List your Wordpress installs plugins and their version and status

Code (Text):

wp plugin list --allow-root
+------------------+----------+--------+---------+
| name             | status   | update | version |
+------------------+----------+--------+---------+
| akismet          | inactive | none   | 4.1.4   |
| autoptimize      | active   | none   | 2.6.2   |
| autoptimize-gzip | active   | none   | 0.1     |
| cdn-enabler      | active   | none   | 1.0.9   |
| classic-editor   | active   | none   | 1.5     |
| disable-xml-rpc  | active   | none   | 1.0.1   |
| native-lazyload  | active   | none   | 1.0.2   |
| nginx-helper     | active   | none   | 2.2.1   |
| sucuri-scanner   | active   | none   | 1.8.24  |
| flush-opcache    | active   | none   | 3.0.2   |
+------------------+----------+--------+---------+

The Wordpress OpCache plugin only has two options to hide flush menu button and to toggle flush OpCache on Wordpress upgrades automatically.

Code (Text):

wp option list --search=flush-opcache-*  --allow-root
+---------------------------+--------------+
| option_name               | option_value |
+---------------------------+--------------+
| flush-opcache-hide-button |              |
| flush-opcache-upgrade     | 1            |
+---------------------------+--------------+

Wordpress OpCache Plugin Settings & Zend OpCache Statistics

So let me know how does your install testing go for Wordpress OpCache plugin and whether you want it auto installed with centmin.sh menu option 22 Wordpress auto installs ?

Reason I plan on adding this is due to Wordpress upgrades modifying and updating PHP scripts, so Zend Opcache having to wait 180 seconds to detect changes can mess with some PHP updated functions unless you do a PHP-FPM service restart to flush Zend Opcache cache. Installing this plugin and enabling flush OpCache cache on Wordpress update, will solve this problem hopefully

 

SSH command line PHP has opcache disabled on purpose to prevent issues via ini settings option opcache.enable_cli=0. If you want to enable it for SSH command line ran PHP, you can create a custom .ini settings file to override opcache.enable_cli=1 as outlined at PHP-FPM - CentminMod.com LEMP Nginx web stack for CentOS. Just like I did in above custom override ini settings file mentioned at /etc/centminmod/php.d/zz-zendopcache.ini

You only need to care about non-SSH command PHP i.e. your web apps if you use phpinfo php page viewed in browser you will see Opcache enabled. When run command via SSH it is disabled for command line PHP only.