Optimization and performance tuning

dadaIMC has been designed to cache content whenever possible without sacrificing the flexibility and customization features that make it unique.

Output from modules is cached to static files in discrete blocks, and is refreshed whenever that content is modified, so you never serve "stale" pages. For the benefit of caching proxy servers, dadaIMC pages will not set cookies or begin sessions unless necessary, and pages are tagged with HTTP headers that allow proxies to serve pages without requesting new versions on every hit.

Nonetheless, there may be times you need to squeeze every ounce of performance from your site. So here are a few tips:

• Turn off any module you are not currently using. Every module that loads requires extra processing, and many (like the Razorwire module) require additional queries with every page load to check for updated content (even if there is none).
• If you are serving content in only one language, and only have one stylesheet available for use, turn off the Home Page module hook that loads quickviews.inc. This will prevent dadaIMC from constantly querying the database for available stylesheets. If you need to offer more than one language, but still use only one stylesheet, you could manually comment-out the stylesheet portion of that same file.
• Browsing without a User account will always be faster than browsing while logged in. Since user accounts generate customized pages, they require extra processing. dadaIMC has been tuned to avoid using sessions or cookies if they are not explicitly requested by some user action.
• The Page Hits module requires a database query to update the page count with every page display. For absolutely optimal performance, turn this module off.
• dadaIMC always explicitly calls the page index.php rather than relying on Apache's DirectoryIndex directive. This means that, under extremely heavy loads, you can set Apache to use index.html index.php in that order, and create a static home page at index.html that is refreshed from the database every 5 minutes. This will allow your site to serve a static HTML page to visitors who access your site using the domain name alone , e.g. http://baltimore.indymedia.org/