Do Drupal websites have bad performance or are heavy? I'm facing a lot of problems with my shared hosting company regarding the performance of my website.

My website is not complicated at all, just text pages, and also some pages using the Views module, I'm not using Panels, and I aggregate my css and js, and also I have 7 image styles (thumbnail,large etc...).

But even so my hosting company told me that I exceeded the memory limit and I have to optimize the website.

I have also another site in a different hosting company .... another problem appears in the database and this is the error message:


  PDOException: SQLSTATE[00000] [1129] Host '...' is blocked because of many connection errors;


I don't know if the problem is because of Drupal or something else.
What's your hosts memory limit?

For MySQL Run this MySQL command

SHOW VARIABLES LIKE 'innodb_buffer_pool_size'


If it's at the default I would see if you can increase it to at least the same size as your database. If you can not, I would look at converting some of your tables to MyISAM.
http://www.mysqlperformanceblog.com/2007/11/03/choosing-innodb_buffer_pool_size/