Mavericks can power down apps when you they’re not in use. For most apps this isn’t a big deal; however, from time to time you may encounter an app that you don’t want to nap when you aren’t using it. To do so, lick on the app and then do a Get Info with the app highlighted. From here, youll see a checkbox for Prevent App Nap. Check that and the app won’t nap!
This setting is kept in ~/Library/Preferences/com.apple.LaunchServices.plist. There is a LSAppNapIsDisabled array. If you create a key with the domain from the app (e.g. net.sourceforge.audacity) and add the signature then you will have disabled App Nap for the app programmatically as well. You can also disable using the NSAppSleepDisabled key against the domain of the app, as follows assuming audacity as well (a bit easier but the same basic result):
defaults write net.sourceforge.audacity NSAppSleepDisabled -bool YES
krypted October 24th, 2013