1. Disk Performance. A non-shared local disk will always give the most consistent and reliable performance. For example, using a host which offers SSD drives or high speed hard drives is ideal.
2. The MySQL Query Cache. The query cache preserves the results for common database queries and can return the results immediately without having to perform them repeatedly.
3. Use of Queries by Your WordPress Themes and Plugins. Out of the box, WordPress is configured to run well, but as we add third-party plugins and themes, we can run into a variety of bad code which can lead to performance issues.
5. Optimizing PHP, which is relatively slow. Faster versions of PHP such as HHVM may be suitable for WordPress in the future, but I’ve read that it’s not yet stable for this task. In the meantime, We offer a list of suggestions: reduce the memory footprint of your scripts, use autoload, use memorization, avoid loops, reduce execution time, minimize the number of files opened to reduce calls to disk and memory usage, and use include and require rather than include_once and require_once.
6. Using Opcode Caching such as APC, an open source caching framework for PHP code.
7. Using Page Caching. The most beneficial technique for scaling a typical website is the caching of pages. Rather than hitting your entire stack with every page request邑ordPress, Theme, Plugins, HTML, and MySQL謡e just retrieve static HTML from the web cache, often from memory. Traffic scaling on an uncached WordPress site can take it down in seconds, whereas traffic scaling on pre-written HTML files from an in-memory cache is massively scalable.
8. Content Delivery Networks (CDNs) are cloud-based caching services for frequently used files and media. With a CDN, it doesn稚 matter where your site is hosted. If you have visitors in other parts of the world, the CDN caches that content close to them and shaves seconds in aggregate off of the total page load time for your site.
9. Other Issues
-Heavy Front End
-Too Many Requests
-No Mobile Optimization