Installing too many plugins can hurt wordpress blog performance as plugins may lead to more queries. One quick way to check the impact of a plugin on mysql server is to enable the query log on the server.
On linux this can be done by editing /etc/my.cnf (or /etc/mysql/my.cnf) on Linux server. Here is the addition/change which is needed
(or whatever log file name you want to use)
Restart the mysql server after this. You use this command on linux (centos):
sudo service mysqld restart
You can view the log file using
tail -f /var/log/mysql_query.log
This can be used for:
- To find out if a plugin is sending too many queries to mysql database. In case it is behaving badly, you may want to look for alternatives.
- It can also help understanding what all tables a plugin is reading and writing. This can used to debug and also to understand data storage structure of a plugin.
Make sure you don’t enable logs in production system permanently. Either you do it on a devel/sandbox setup of do it for a short duration.