Photos uploading every picture to iCloud *again* after moving library to new Mac?

[canyonblue737]

I'm moving a large 400GB Apple Photos library to a new Mac. This library is full synced with my iCloud account.

I copied the library by dragging it to a new 2TB SSD external drive. I then plugged this drive into my new M1 MacBook Air. I double clicked to open the library on the external drive and it asked me if I wanted to use this library, I selected yes, and immediately Photos opened with the full contents of the library visible (some 66,000 photos). I then went to Preferences, made the new library on the SSD my "System Library" and then I turned on iCloud and "download original" on.

Immediately I had two issues: 1) new photos taken by my iPhone were not appearing in the library despite iCloud being turned on and 2) it stated roughly "66,000 photos uploading". This was concerning because those 66,000 photos were ALREADY on iCloud so I stopped this process and then deleted the library. Should I have waited it out? Was it REALLY uploading them all again? Would I have had duplicates and doubled my library to a terabyte?

Against my better judgement I deleted the library and started over. This time I just turned iCloud on and pointed it at any empty folder on my external drive and had it create a new library. Within 30 minutes it had downloaded low res versions of ALL 66,000 photos and was syncing nicely if I took a new picture on my iPhone. However it started the process of "downloading originals" but it became obvious the downloading of those originals was PAINFULLY slow despite gigabit speed internet and no data caps.

So... now I'm here for help... what do I do? I want the easiest way to put my entire Photos library on an external SSD, plug that SSD into a new Mac and a fresh Photos, make it the primary library and have it work with iCloud just like my old Mac. What am I doing wrong?

Thanks!

 

[lolcats5000]

No answer here! i cant bring myself to cancel the upload, it CANT reupload everything, not even Photos, which admittedly is devastatingly stupid, would be that stupid.

 

[mk313]

Good luck. I have no ideas on how to fix it. But I will say that in my experience, the iCloud works best when NOTHING else is going on in the background at all. When I got my new Mac, I had a smiler issue & it was taking days. I'd leave it on overnight & only make a little progress. Then I read somewhere that it's designed to run in the background, and on a whim, I closed out every other program and left icloud on overnight. By the morning, everything had synced. So I'm guessing that whenever any other process started to run (email, time capsule, whatever) overnight, it would pause the iCloud syncing until that process ended. Hopefully that helps to speed up the sync for you.