Wordpress Sudden high mysql usage problem

Wordpress ? what web app ?

If running Centmin Mod 123.09beta01 or higher, you will have access to a cminfo top command which can also provide a summary of statistics - some of which are explained in info and linked articles below.

FYI, CPU load optimal is 1.0 per cpu thread so 8 cpu thread normal = 8x1 = 8.0. 16 cpu server normal is 16x1 = 16.0

so cpu load of 8 for

• 2 cpu server = 8/2 = 4.0 load average
• 4 cpu server = 8/4 = 2.0 load average
• 8 cpu server = 8/8 = 1.0 load average

When you type top command, hit number 1 to break down per cpu stats

Centmin Mod is provided as is, so troubleshooting load issues is left to end user to do. However, there's many linux tools and scripts that can help you figure out what was causing the load issues and when.

If you're providing info on this forum, more info might be helpful

1. What version of Centmin Mod ? .08 stable or .09 beta ? If .09 beta when was it installed and when was last time you updated ?
2. What's your VPS/Server hardware specifications ? cpu type ? memory available ? disk space ?
3. Who's your web host ? Different hosts have different limits for server resource usage and some are more restrictive that others so it could just be their resource usage policy you tripped which may or may not be restrictive. If restrictive, then real solution would be finding a better web host. If not restrictive, then it's finding out what caused high cpu load.
4. If running Centmin Mod 123.09beta01 or higher, you will have access to a cminfo top command which can also provide a summary of statistics - some of which are explained in info and linked articles below.

Tools and commands you will want to read up on and learn for basic system admin tasks and troubleshooting.

• 20 Command Line Tools to Monitor Linux Performance
• 13 Linux Performance Monitoring Tools - Part 2
• 80 Linux Monitoring Tools for SysAdmins - Server Density Blog
• Amazing ! 25 Linux Performance Monitoring Tools
• 20 Linux System Monitoring Tools Every SysAdmin Should Know
• My mysqlmymonlite.sh script can help with that mysqlmymonlite.sh Addon | Centmin Mod Community README text file has instructions for setting up a cronjob to email you reports i.e. every 10/15min or every hour.

Notes:

• Centmin Mod already installed Glances tool. It can be invoked from SSH command glances or top2. Official Glances site at nicolargo.github.io/glances/ and documentation here.

For example what's output for these commands

Code (Text):

top -bn1

Code (Text):

ps aufxw

Code (Text):

sar -q

Code (Text):

sar -r

Code (Text):

sar -q -f /var/log/sa/sa$(date +%d -d yesterday)

Code (Text):

sar -r -f /var/log/sa/sa$(date +%d -d yesterday)

If you want to look at per process usage stats use pidstat run pidstat every 1 sec for 5 runs and sed is just to replace your main hostname with word hostname so mask your domain for posting on public places

Code (Text):

pidstat -durh 1 5 | sed -e "s|$(hostname)|hostname|g"

for posting code you might want to use CODE tags for code How to use forum BBCODE code tags

 

yeah cache enabler can't do logged in user caching but i personally haven't used wp super cache for logged in users so can't see first hand. You can follow the cache enable removal guide at https://community.centminmod.com/threads/disable-or-remove-keycdn-cache-enabler.15657/ first and try wp super cache plugin install though it would be missing some of the stuff centmin.sh menu option 22's wp super cache install does but you can manually uncomment the wp super cache include file in your nginx vhost

edit: question for cache enabler logged in user caching posted ages back at Caching for logged in users ? · Issue #19 · keycdn/cache-enabler interesting a forked version of cache enabler may have logged in user caching # This is a combination of 20 commits. · RedCastor/cache-enabler@7ee2303 and # This is a combination of 21 commits. · RedCastor/cache-enabler@3bdb96a ???

forked version differences keycdn/cache-enabler

edit: ok forked version doesn't have logged in user cache from change log

Code (Text):

== Changelog ==
= 2.0.2
* Add bypass if WP_CACHE defined and false
= 2.0.1
* Add user can editor clear cache options
= 2.0.0
* Add some third party plugins functionality (woocommerce and wpml)

edit: looks like it wasn't a fork but just a fork for pull request sake Add cleaner class for third party plugins compatibility by auban · Pull Request #36 · keycdn/cache-enabler ?

 

everything mentioned in https://community.centminmod.com/threads/sudden-high-mysql-usage-problem.17199/#post-72713 is a start

 

happy holidays !

what was the widget/plugin name ?

sounds like cache enabler bug then so might want to check with keycdn folks keycdn/cache-enabler

tried disabling cache enabler plugin from wp admin plugin management page, and re-enabling it ?

 

If you ran centmin.sh menu option 22 and selected KeyCDN Cache Enabler as your Wordpress caching choice but now want to disable Cache Enabler, you can do so using following steps below:

1. Disable Cache Enabler WP Plugin from WP Admin Plugin area

2. In your nginx domain.com.conf and/or domain.com.ssl.conf vhost config file, comment out (add hash # in front) the Cache Enabler try_files rule and uncomment the standard Wordpress try_files rule for WP permalinks

Code (Text):

  # for wp cache enabler plugin
  #try_files $cache_enabler_uri $uri $uri/ $custom_subdir/index.php?$args;

  # Wordpress Permalinks
  try_files $uri $uri/ /index.php?q=$uri&$args;

3. In your nginx domain.com.conf and/or domain.com.ssl.conf vhost config file, comment out (add hash # in front) the include file for Cache Enabler where yourdomain.com is your domain name

Code (Text):

  #include /usr/local/nginx/conf/wpincludes/yourdomain.com/wpcacheenabler_yourdomain.com.conf;

4. Then restart nginx + php-fpm services and run nginx config check to see if the nginx configuration is working

Code (Text):

nginx -t
nprestart