If you are a frequenter of popular social sites such as Digg, you may have noticed that sometimes a blog will be down when you try to visit it. Unfortunately, unless a website has a dedicated server, it is going to often be difficult for a blog to survive the Digg effect and avoid some downtime.
While this definitely can be considered a problem, I would consider it to be a good problem to have because it means you are writing some great content. As a WordPress user, there are options available to help you avoid downtime for your blog in the form of WordPress plugins.
Up until recently the WP-Cache 2 WordPress plugin was the primary plugin people used to reduce serverload, but recently a better version of the WordPress plugin was created, called WP Super Cache.
Here is some information about WP Super Cache straight from the author:
A classic method of preparing an under powered site for a Digg front page appearance or a Slashdotting has been to manually save copies of dynamically generated pages, and place them in directories that match the permalinks structure. This method of performance enhancement does help servers handle a higher load without crashing, but is only effective when an oncoming rush of traffic can be anticipated. WP-Cache alone, while helpful, is not adequate in many cases, so WP Super Cache was created to effectively mimic the manual page caching method, but to handle it in an automated fashion.
When a visitor who is not logged in, or who has not left a comment, visits they will be served a static HTML page out of the supercache subdirectory within the WordPress cache directory. If you navigate to that directory you can view an exact replica of your permalink structure as well as the HTML files within the directories. To determine if a page has been served out of the Super Cache, view the source and the last line on the page should read
<!-- super cache -->or
<!-- super cache gz -->.
If a visitor who is logged in or who has left a comment views a cached page, it will be served from the standard WP Cache function and the last line in the source code will read
<!-- Cached page served by WP-Cache -->
In order to install this plugin, you simply need to go through the normal process of uploading and activating it. It will then create an Options panel where you can set your desired cache time.
Note: For maximum performance, it is recommended to also download XCache and install it. You can then use the XCache WordPress plugin to improve WordPress load times even further.