I have a big problem.

I have a dedicated server with 1 website.
Sometimes, the main page is loaded very fast (contains MYSQL CONNECTION).
But, sometimes I wait too long time and no thing appears.
And sometimes, "Error connection to database" appears after a long time of waiting.

NOTE: All pages without Mysql connection are loaded very fast.
WHY??????????????

dani,

It sounds like your MySQL server has some performance issues. The fact that your main page loads "very fast" despite its script connecting to the database may speak to some resource allocation problem (e.g., connection pooling). You may want to touch base with your ISP to see if they can provide any performance metrics on your MySQL server.

Some ISPs have the web server double as the MySQL server. Other ISPs have dedicated MySQL servers. I would touch base with your tech support to see if they have any information.

In the meantime, consider posting your problematic code here so the WT community can evaluate it for you.