Occasionally when I am using iPhoto an app with a generic white Lego piece icon opens on the dock with the name "com.apple.MediaLibraryService.xpc".
Activity Monitor lists it as "(Not Responding)" and shows it using a pretty large amount of CPU time. When I quit iPhoto its % CPU drops to zero, but it remains in the dock and remains unresponsive in Activity Monitor.
It doesn't happen every time I use iPhoto, and there doesn't seem to be any particular action that triggers it to open. It does seem to correspond to a general slowing of responsiveness (already not great) in iPhoto. I am generally loathe to force quit something if I don't know what it is.
Does anyone know what this app does, why it is opening, and how to prevent it from hogging my CPU when I'm working?
Best Answer
The com.apple.medialibraryservice.xpc is a process used for a number of Apple-specific applications and services, including: indexing photos through iTunes (when syncing), and importing and exporting images in iPhoto.
Some users have reported that this happens when importing slo-mo videos into iPhoto from the iPhone 5s. This could be happening to you when syncing your iOS device--you can disable automatic syncing for iTunes as a temporary fix to see if helps your situation.