When your Mac's storage is almost full, macOS Sierra will help you make some space.

You might have come across that dreaded message: "Your startup disk is almost full." The computer wants more space, and the only way to make that happen is by deleting files. But, how do we know what files to delete? In OS X El Capitan, we have to manually dig through old files and delete them as we find them, like some kind of animal. With macOS Sierra, Apple is making it easier to make space by allowing us to set up Optimized Storage, which features automatic iCloud storage for older files and the ability to review and delete files we don't use on our Macs anymore.

Files can be automatically stored in iCloud

With Optimized Storage, you can make room for new files by keeping older ones in the cloud. When your storage gets low, only recently opened files will be kept on your Mac. Below is a list of files that will be automatically stored in iCloud when you enable to storage-saving featue.

  • ePub books you've read
  • Books in iBooks you've read
  • Old screenshots
  • iTunes U courses you're not using
  • Full-resolution photos
  • Mac App Store apps you're not using
  • Old presentations
  • Old PNGs
  • Old RAW files
  • Old text files
  • Old word processor documents
  • Old documents
  • Languages you're not using
  • Played iTunes podcasts
  • Old home videos
  • Fonts you're not using
  • Old Mail attachments
  • Old illustrations
  • Movies in iTunes you've watched
  • Dictionaries you're not using
  • Viewed iTunes TV shows
  • iTunes songs you don't listen to
  • Old clippings
  • Old JPEGs
  • Old spreadsheets
  • Instructional system videos

Files can be automatically deleted from your Mac

With Optimized Storage, you can get rid of files you'll never need again. Items like redundant Mail data and Safari Web Cache will automatically be removed from your Mac. Items that have been in your trash for more than 30 days will automatically be deleted. You'll also be able to reduce clutter by reviewing and deleting recommended older documents stored on your Mac. Below is a list of the file types that can be deleted and removed from your Mac with Optimized Storage.

  • Redundant Mail data
  • Previous OS X installers
  • Apple Music playback caches
  • Safari Web Cache
  • Cached iBooks animations
  • Event logs
  • Cached Map tiles
  • Fault and error logs
  • iTunes inactive downloads
  • Cached iBook covers
  • Trash after 30 days
  • Configurator iOS files
  • Quick Look thumbnails
  • iTunes IPSW files
  • State dump logs
  • iBooks inactive downloads
  • Archived Safari Reading List
  • Persistent logs
  • Mac App Store inactive downloads
  • Xcode caches
  • Old iPhone backups
  • Configurator inactive downloads
  • iTunes orphaned database temporary files
  • TTL log files

With Optimized Storage on macOS Sierra, it will be a lot harder to get to that point when you receive that dreaded message, "Your disc space is getting full." When you do, Apple's storage-saving features will make it easier to keep your Mac clear of useless caches and older files that you just don't need anymore but forgot you had.