Everyone please be very careful when deleting data from the iCloud in Settings! If you make a local back up like I did, trying to restore it later will result in Notes synching with an empty iCloud causing all your data to be lost. There doesn't appear to be a way to easily backup your Notes, delete iCloud Notes data and then simply restore the Notes locally.
Here is the laborious process I took yesterday to remove 1,500 Notes (1.4GB) from iCloud and then restore them back again. These were complex Notes with documents, photos, drawings, etc. contained within. Most of the Notes were exported from Evernote and then imported into Notes a few weeks ago (via XML export/import).
So far YES, the lag and slowness of Notes has almost completely gone from my iMac and two IOS devices. There is sometimes a slight stutter upon first launching Notes when iCloud sync starts up.
---- OPTION A ----
Some steps may not be required… this is just how I ended up completing everything while also turning my hair grey from stress. See Option “B” further below for my alternate suggestion. Follow these directions at your own risk (!):
1. Backup both Notes local folders on Mac:
Previous version of Notes (probably not needed but I did it anyways…):
~/Library/Containers/com.apple.Notes/Data/Library/Notes/
New version of Notes:
~/Library/Group%20Containers/group.com.apple.notes/
2. Settings -> iCloud -> Manage —> Notes -> Delete Documents and Data
3. Turn off Notes in iCloud on Mac & IOS devices
4. Wait few minutes
5. Turn on Notes in iCloud on all devices
6. Allow devices to sync w/ empty data
7. On Mac, disable network/Internet connection. This will prevent iCloud from deleting your local Notes immediately after trying to restore it.
8. Restore notes backup folders using backups made in step 1.
9. You may need to enable showing your local Mac notes. In Notes, go to menu bar -> Notes -> “On My Mac” Account
10. Drag all your Notes folders/notes from "iCloud" to “On My Mac”
11. This will be a slow process (even on an iMac5K w/ i7 and SSD) and Notes may appear to hang multiple times for every folder moved around. You will see the spinning beach ball a lot.
12. Enable network/Internet connection
13. Allow iCloud to sync again. Will take a few minutes even though there is nothing to sync.
14. Now start moving you Notes and folders back from “On My Mac” to “iCloud”. Again this will be a slow process with Notes hanging at times.
15. Once all folders are moved, allow iCloud to finish synchronization.
16. Go to your other Macs & IOS devices and allow them to sync as well. I have a 180Meg down / 10 up Internet connection so the sync was fairly quick.
---- OPTION B ----
Now based on hindsight, I think the following steps would be improved instructions for anyone trying it out. Follow these directions at your own risk (!):
1. Just in case, backup both Notes local folders on Mac:
Previous version of Notes (probably not needed but I did it anyways…):
~/Library/Containers/com.apple.Notes/Data/Library/Notes/
New version of Notes:
~/Library/Group%20Containers/group.com.apple.notes/
2. You may need to enable showing your local Mac notes. In Notes, go to menu bar -> Notes -> “On My Mac” Account
3. Drag all your Notes folders/notes from "iCloud" to “On My Mac”. This will be a slow process (even on an iMac5K w/ i7 and SSD) and Notes may appear to hang multiple times for every folder moved around. You will see the spinning beach ball a lot.
4. Settings -> iCloud -> Manage -> Notes -> Delete Documents and Data
5. Allow all other Macs and IOS devices to sync with empty data.
6. Turn off Notes in iCloud on Mac & IOS devices
7. Wait few minutes
8. Turn on Notes in iCloud on all devices
9. Now start moving you Notes and folders back from “On My Mac” to “iCloud”. Again this will be a slow process with Notes hanging at times.
10. Once all folders are moved, allow iCloud to finish synchronization.
11. Go to your other Macs & IOS devices and allow them to sync as well. I have a 180Meg down / 10 up Internet connection so the sync was fairly quick.
