Using Joomla

Clean Cache

The term cache (pronounced like the word “cash”) might be a fairly common word, but not everyone knows exactly what it is. Essentially, it’s a space where items can be quickly stored and reused in order to save resources and time.

Each time you view a page on your website, Joomla does a lot of work to build each piece of the page, and then puts them together like pieces of a jigsaw puzzle. When the page is complete, the web server sends the rendered code back to your browser where you actually view the page.

When caching is turned on, the individual puzzle pieces are saved to files after they are built. The next time someone needs that puzzle piece, Joomla will get it from the file instead of working to build it again. After a set period of time, that puzzle piece will expire and Joomla will build a new puzzle piece and place it into cache. Typically, cache refresh happens every 15 minutes. Cache settings can be found in Global Configuration to specify the amount of time to cache these puzzle pieces.

On smaller sites, caching serves little purpose. On large sites, caching is vital to minimize server load time, which, in turn, greatly improves your site’s performance.

To access the Cache Manager, click Tools→Clean Cache. Figure 16-3 shows the Cache Manager with a few cached items. To clear them, check the ones you want to delete and then click Delete.

Figure 16-3. Cache Manager–Clean ...