A few months back I wrote about RSS bandwidth consumption, and this subject is again in the news following Chad Dickerson’s recent InfoWorld column about his love/hate relationship with RSS. Dickerson notes that desktop RSS readers which hit a feed too frequently – and then download the feed even when it hasn’t changed – are resulting in a huge server load.
However, as Dare Obasanjo points out, many of those complaining about RSS bandwidth consumption fail to configure their own servers to address the problem. Dare shows that InfoWorld’s feed supports neither GZip encoding nor conditional HTTP Get, both of which would dramatically decrease RSS bandwidth consumption. The latest RSS reader stats show that all the major ones support these techniques, so make sure your server (and/or the feed itself) supports these techniques. If you have a static feed, chances are your server handles this for you – but if you have a dynamic feed (i.e.: one created on-the-fly with PHP or ASP), you may need to make some changes.
In the past, raising this topic has been followed by naive calls to stop using desktop RSS readers in favor of web-based applications, since web-based aggregators consume less bandwidth. I’m far too biased to argue about desktop vs. web aggregators, but the argument is moot since many people find the UI and feature set of web-based apps too limiting for their needs and will always want a desktop application (witness Outlook vs. HotMail). Arguing for either type of application is pointless, since each will be around for a long time.
BTW, I’m glad to see that Sam Ruby is proposing updating the Atom spec and the feed validator to support HTTP conditional get. My guess is that a lot of bandwidth will be saved once the feed validator warns about feeds that don’t take advantage of the If-Modified-Since and If-None-Match HTTP headers.
Oh, and since I mentioned RSS reader stats, I have to get this off my chest: server stats are not an accurate representation of the popularity of individual RSS readers. A number of RSS readers default to checking for updates every hour, whereas FeedDemon defaults to checking every three hours. So, three times as many people would need to use FeedDemon for it to be ranked equally with these other apps.