Getting your battery draining fast, due to the mdnsd process, or your Facebook app doesn’t show content and isn’t responding ?
Then… you’ll most likely have to uninstall your Facebook app to get your battery back for other uses.
The mdnsd process is a DNS daemon – meaning, it is a supporting process for other apps to query websites, running in background. It might use too much battery due to Facebook app, or another one doing a lot of Internet queries (for example, Firefox). You can’t stop it directly, but you can try stopping the apps using it.
Before uninstalling the application, try the following : clear the cache, and force the app to stop. It sometimes is enough, but not always, and, in any case, won’t be sustainable, and will have to be done again.
If this isn’t enough, try also stopping the Messenger app – it sometimes help.
Meanwhile, until a good fix is created for your phone, uninstalling the app does the trick – and you can access the mobile version on a web browser.