If you are looking to improve the performance of specific pages of a website, or the overall performance of a website, you should consider the following (
Improve Website Performance):
DNS requests will slow a web page: This includes displaying ads from an external source, as well as displaying feed content on a webpage.
Complex database queries returning and displaying a large set of results, or performing calculations and comparisons on the data can also slow a page or website down significantly.
You can
optimize a website for performance by reducing the amount of processing and the number of external requests for information when pages are being loaded on a website. Instead, background scripts or Cron Jobs can be executed by the server on a periodic basis (every 5 minutes) to complete the processing, and html from the data retrieved from external sources (usually requiring a DNS request). This pre-formatted html can the be stored in a separate database table for retrieval when displaying on a web page.
Web Pages on your site can the be configured to retrieve the processed information from the database as pre-formatted html to display directly on the page. This will be much quicker than reloading and processing data from external sources or processing a large amount of data from the website's database in a single request.
For more information, see
Improve Performance for Websites with a Database Back-end & Dynamic Content
