I clicked and dragged them into iCloud, but my startup disk is still full. I'm not sure if my iPhoto and music is really on the cloud?
It takes a long time to upload and it will not work this way. iPhoto needs the library on a locally connected volume. It cannot be on a network drive. Writing to an iPhoto library while it is on iCloud Drive, sitting in a Dropbox, or any NAS may corrupt the iPhoto Library. A library is a package of related files, referencing each other. Syncing across a network will break these references and you risk to lose your photos. I tested with three small iPhoto libraries and none were readable after uploading to iCloud Drive.
Move the iPhoto library back, as soon as the upload finishes and you no longer ar seeing any loading bars. Don't try to move as long as you are seeing progress bars.
To save space on your mac, move the iPhoto Library to a locally mounted disk as described in this document:
Use locally mounted Mac OS X Extended volumes for your Aperture library
Also, if you move your documents from a Mac to iCloud Drive, you will not save any space on your Mac, because iCloud Drive is keeping local shadow copies of all files and folders on your Mac. You need as much storage locally on your Mac as you are using on iCloud Drive.
iCloud Drive is a central storage in iCloud that is automatically updating all local copies.
See: iCloud Drive FAQ
Cloud Drive FAQ
With iCloud Drive, you can safely store all your presentations, spreadsheets, PDFs, images, and any other kind of document in iCloud. Documents you store in iCloud Drive will be kept up to date across all of your devices, and you can access them from your iPhone, iPad, iPod touch, Mac, or PC.
Here's what you can do with iCloud Drive:
- Store and access all of your documents in one place from any of your devices
- Keep files and folders up to date across all your devices
- Create new files and folders from iCloud-enabled apps
- Work on the same file across multiple apps ......