Photos database on external SSD and Time Machine compatibility? EDIT: * Samsung T7 SSD benchmarks inside *

[EugW]

Hi. My iMac's internal 1 TB SSD is getting fuller than I'd want so I was thinking of moving my Apple Photos database to an external SSD. Some questions:

1) AFPS or HFS+? I'm thinking AFPS, just because both my primary iMac and my primary MacBook are APFS on Big Sur.

Move your Photos library to save space on your Mac - Apple Support

To save storage space on your Mac, you can move your Photos library to a different storage device.

support.apple.com

2) Is Time Machine an issue? I know it can back up external drives, but the stuff at the bottom of this article confused me regarding backing up Photos libraries on external drives:

Where is it safe to store a Photos Librar… - Apple Community

discussions.apple.com

3) The external SSD is USB-C and thus won't have TRIM. Will that be a problem? The database is currently about 500 GB and the drive is 1 TB. Thunderbolt drives are currently cost prohibitive, but I could get a larger non-thunderbolt drive if that would help. I will not go with a hard drive. SSD or nothing, because of @Weaselboy's post:

Apple Photo's Library on SSD

I have an older Photos library I keep on an external (USB3) SSD and I previously had it on a external HDD. I can promise you there is a night and day difference. If you can afford the external SSD, you will not regret it.

forums.macrumors.com

 

[EugW]

Well that sucks.

I moved the 503 GB Photos library to my 1 TB SSD. I then made the new destination the primary Photos system library as per Apple's instructions above. However, moving the library deactivates iCloud Photos syncing, until I manually reactivate it.

So, I then tried to reactivate iCloud Photos but it said I may not have enough space and therefore I have to optimize photos in order to make it work.

I assume it's because 503+503 is > 1TB. Dammit Apple, you always have to made this way too complicated. This is stupid. They need to include a migration feature that gets around this.😖

So, right now I'm in the process of moving the Photos library again, this time to a 2 TB hard drive. Then I will try this process again. If that works then I guess I will buy a 2 TB SSD and do it all over again.

---

BTW, on another note, I was clearing out my old iTunes directory and realized I still had a directory of downloaded iOS applications from eons ago when that was still a thing. Deleted that and freed up 32 GB of space. Also, it turns out if you locally downloaded iTunes movies which had iTunes Extras and then deleted the movie, it deleted the movie but not the Extras. So, I had a bunch of Extras there taking up space too. Freed up another 3 GB of space there.

 

[Brian33]

1) AFPS or HFS+? I'm thinking AFPS, just because both my primary iMac and my primary MacBook are APFS on Big Sur.

For an SSD, I'd go with APFS, as it's designed to be efficient for solid-state storage devices. I can't think of any reason to go with HFS+.

2) Is Time Machine an issue? I know it can back up external drives, but the stuff at the bottom of this article confused me regarding backing up Photos libraries on external drives:

The way I read it, it's saying (1) not to put your Photos library on the same external drive as your TM backup (good advice, since a single drive failure could wipe out both), and (2) there was a bug (now fixed) that prevented TM from successfully backing up Photos libraries that were on external drives.

I think TM will have no problem with your setup. If you're worried, do a spot-check of the backup on the TM drive. (You can just go in with Finder, use right-click to "Show Package Contents" on the xxxx.photoslibary file, and look for your images within the file structure.) Even better you could do a test restore of the library to an spare volume, and open it in Photos temporarily. TM does fine backing up external drives in general (though I don't have my Photos library on my external).

3) The external SSD is USB-C and thus won't have TRIM. Will that be a problem?

I don't know for sure, but I wouldn't worry about it. So performace might be affected somewhat; but I doubt you'd notice it. By my understanding, the SSD's controller's garbage collection algorithm will still work.

 

[Brian33]

However, moving the library deactivates iCloud Photos syncing, until I manually reactivate it.

So, I then tried to reactivate iCloud Photos but it said I may not have enough space

I wonder if iCloud will be smart enough to know that it doesn't need to download anything.

The error seems weird. It seems like Photos is insisting that your drive be big enough for two copies of your library, as if it is "expecting" to download everything from iCloud and add it to what you've already copied to the external. I guess a different approach would be to create a new empty photos library on the external, then turn on iCloud syncing, and let Photos just download everything...

 

[EugW]

Performace might be affected somewhat; but I doubt you'd notice it. By my understanding, the SSD's controller's garbage collection algorithm will still work.

Yeah, I think you’re right, as long as keep some of it empty. When I was running a Samsung 840 SSD over Firewire without TRIM it was OK for a while, but then when it got near full, it would slow to a crawl for photo transfers.

I got a new Samsung T7 2 TB SSD today. I’m going to move some other data to this drive too, but it will be 2/3rds empty initially.

I wonder if iCloud will be smart enough to know that it doesn't need to download anything.

The error seems weird. It seems like Photos is insisting that your drive be big enough for two copies of your library, as if it is "expecting" to download everything from iCloud and add it to what you've already copied to the external. I guess a different approach would be to create a new empty photos library on the external, then turn on iCloud syncing, and let Photos just download everything...

Yes, it seems Photos just takes the worst case scenario and assumes you need a drive at least as big as the combination of both sets of pictures. However, from what I've read, I think it also wants a buffer on top of that too. I don't think it will work if you have just enough space. You need more than just enough.

I thought about doing what you’re saying and just letting the Mac download everything from iCloud, but I want to keep the original library intact just in case. Eons ago, I ran into an issue where iCloud mistakenly stripped some “Live” parts of Live Photos. It was a very painful process to restore everything (from local backups). Since I know everything is intact right now, I may as well keep the original library since I can. I’ve been meaning to get a new USB 3.1/3.2 gen 2 drive anyway, just because. BTW, I benched this new Samsung T7, on APFS:

Pretty decent for an external USB drive. For a real world test the 502 GB Photos library took about 25 mins to transfer over. That works out to about 335 MB/s. Not bad, but it was from T5 to T7 so in reality it wasn't really testing the T7, as the T5 was the bottleneck.

I also tried this on a 2 TB hard drive. It was an old Seagate Barracuda LP from 2011, freshly formatted. The transfer of the 500 GB library to that drive wasn't too bad... but the first time I opened the library was a freakin' disaster. It took 20 minutes, and no I'm not exaggerating. WTF?!? I initially thought it had crashed, but the drive access LED was busily flashing away and I could hear the seeks, so I knew it was doing something. So I just let it sit and then finally after 20 minutes the database opened. Holy crap! After that loads were under 10 seconds but it would take time for images to go from pixelated to full rez. Yes it's an old drive, but still, I wouldn't have expected it to be that bad, esp. with a USB 3.0 connection.

In contrast, the first load was quite fast on the Samsung T7 SSD. I didn't time it but was just a few seconds. Same with the T5. What a contrast! Seconds vs 20 minutes. The update process was also much more noticeable on the hard drive. With the hard drive, the drive head was ticking away all day long under constant use. The SSD is silent of course.

BTW, there were occasions where I wondered if the T7 might be ever so slightly faster in real world use than the T5 (which has considerably slower transfer speeds in benchmarks), but mostly they felt pretty much identical in Photos, so it might just be placebo effect. That is to say, the T5 feels very fast as well. The T7 may be faster in some usage but for Photos, but most of the time the extra speed is probably wasted because the T5 is already more than fast enough. The 2 TB T5 was only 11% cheaper though so I figured I'd splurge to get the T7. In contrast, the Samsung X5 Thunderbolt SSD was over twice the price of the T7. Damn.

So, overall, I'm very pleased with my Samsung T7 purchase.

And yes, Time Machine seems to work fine now with external drives, as long as you tell Time Machine not to ignore them. As you can see in this screen grab, the Time Machine Preferences automatically excluded my T7, so I'll have to manually delete that exclusion, which is just a click of a button.

 

[JourneyB4Destination]

So are you putting your photos and time machine backups both on the T7? Is it partitioned into drives?

and how is using only 1TB for time machine backups for the internal 1TB? I keep reading that it’s best to use a 2TB + drive for time machine backups of a 1 TB internal.
I’m in a similar situation as you except I don’t pay for iCloud storage and plan to break my library into 2 photo libraries: last 2-3 years I’ll keep on my internal and each year offload one years worth to the 2nd library that’ll hold all older photos. 2nd library will be on the external drive (currently about 4or 500GB)

I also plan to get backblaze personal for cloud “backup” but their personal plan excludes any drive with time machine backups hence I will have to keep time Machine backups on a separate disk or partition.

I myself am trying to decide between the t7 or t5 1TB for the 2nd photo library primarily and may either get a 2nd 1TB for time machine backups or go with a partitioned 2TB version. Or tempted to try an nmve 1TB in an enclosure... just can’t decide yet.

 

[EugW]

I have two external drives. A spinning hard drive for Time Machine, and a T7 for Photos. Each are 2 TB in size.

 

[JourneyB4Destination]

I have two external drives. A spinning hard drive for Time Machine, and a T7 for Photos. Each are 2 TB in size.

Ah gotcha. May I ask what external hdd you use how how’s it’s fairing for TM?

 

[EugW]

The Time Machine drive is a Toshiba I got ages ago. I don't remember the specifics but it works fine and is silent.