Using external drive for Photos library on M1 iMac

[acousticbiker]

I’m moving from an Intel to M1 iMac and, given the cost of internal SSD space, considering using an external SSD for Photos library (I have 500GB+ in photos and videos). I do use iCloud Photo Library.

- Will I notice any difference in performance?
- Would there be any difference in performance of this setup depending on whether I choose the 7-Core or 8-Core GPU version (factoring in not only the extra GPU core and extra fan but also any difference in the ports - I know there’s 2 vs 4 ports but wasn’t sure whether they also differed in speed)
- I’m trying to decide between 1TB and 2TB. I don’t expect to get to fill a 1TB any time soon but am wondering whether there’s a performance hit when approaching a certain percentage of full
- Is there any particular spec to the external SSD I should look for to optimize performance?
- Would 8GB vs 16GB RAM make any difference in performance for this specifically?
- If there’s no way to get around a performance hit, is it possible to use Photos in ‘Optimize Mac Storage’ mode on the iMac internal drive while backing up the full images on the external drive?
- Any downsides besides any performance hit I should be aware of?
- When I do make the switch, would there be any difference in directly transferring the Photos library from my current iMac to the external SSD vs downloading to the external SSD from iCloud Photo Library? I’d rather do the former to save bandwidth (home internet data is capped) but wasn’t sure whether change from Intel to M1 and/or regular hard drive (current iMac) to SSD would justify downloading

 

[satcomer]

Save up you money for fast NVME external Ising the quickest dive in the thread Thunderbolt 3 name enclosures thread because it will show you the quickest dive you can make!

For NAS for long term storage search for Synology or another, your choice!

 

[EugW]

Just get a Samsung T7 Shield external USB-C SSD. Performance will be fine unless you're constantly backing up 100 GB at a time or something.

BTW IIRC, you need the drive to be more than twice the size of your library when you're setting it up for the first time.

 

[acousticbiker]

BTW IIRC, you need the drive to be more than twice the size of your library when you're setting it up for the first time.

Wow, if true, that’s super helpful as I try to decide what size drive to get. Does anyone else remember whether this is the case?

 

[EugW]

Wow, if true, that’s super helpful as I try to decide what size drive to get. Does anyone else remember whether this is the case?

I don't remember the details, but I think it may have been something to do with when I was doing a transfer of the drive to a new setup.

 

[smoking monkey]

Just get a Samsung T7 Shield external USB-C SSD. Performance will be fine unless you're constantly backing up 100 GB at a time or something.

BTW IIRC, you need the drive to be more than twice the size of your library when you're setting it up for the first time.

I've just done this for the wife on an Air M1 7C 8Gram 1TBHD. She has a 588gig photo library and I copied the library over via the icon from the photos folder to the external T7 1TB Sammy HD. With the external turned on and plugged in she then had two identical libraries. Then I did the - Hold down option and open photos (there may have been a couple of other steps, you can find the steps on the net pretty easy). So now she keeps her videos on the external and photos on the internal and both can be backed up to time machine if you go into time machine settings and MINUS the external from the exclusion list (the first back up took forever though).

Using the OPTION + OPEN PHOTOS APP you then get the choice of which library you want to open as long as the external is plugged in.

Be careful though because the Photos App doesn't really give you a good idea of which library you have open. There should be a library name at the top, but there isn't.

I had zero issues with the External needing to be more than double the size of the library (588g v1TB). I did this a couple of months ago and was updating her library and backing it up just yesterday and everything is totally fine.

copying your music and photos libraries used to be a big PITA, but it's super easy now.

EDIT: The sammy gets hot. Put a fan on it while you're doing large amounts of copying.

 

[EugW]

I've just done this for the wife on an Air M1 7C 8Gram 1TBHD. She has a 588gig photo library and I copied the library over via the icon from the photos folder to the external T7 1TB Sammy HD. With the external turned on and plugged in she then had two identical libraries. Then I did the - Hold down option and open photos (there may have been a couple of other steps, you can find the steps on the net pretty easy). So now she keeps her videos on the external and photos on the internal and both can be backed up to time machine if you go into time machine settings and MINUS the external from the exclusion list (the first back up took forever though).

Using the OPTION + OPEN PHOTOS APP you then get the choice of which library you want to open as long as the external is plugged in.

Be careful though because the Photos App doesn't really give you a good idea of which library you have open. There should be a library name at the top, but there isn't.

I had zero issues with the External needing to be more than double the size of the library (588g v1TB). I did this a couple of months ago and was updating her library and backing it up just yesterday and everything is totally fine.

copying your music and photos libraries used to be a big PITA, but it's super easy now.

EDIT: The sammy gets hot. Put a fan on it while you're doing large amounts of copying.

I don't remember exactly but maybe I already had the database on the drive and when I tried to open it it made a duplicate instead of just opening it. Not sure though. All I know that a 500+ database wouldn't fit on a 1 TB drive. It kept on saying I didn't have enough space until I switched to a 2 TB drive.

 

[acousticbiker]

I've just done this for the wife on an Air M1 7C 8Gram 1TBHD. She has a 588gig photo library

Thanks for sharing! Mind if I ask why you went through this process with a 588GB library on a 1TB internal drive? Guessing she has other stuff taking up a lot of space. I don’t have much else taking up much space and trying to determine whether a 1TB internal drive may be enough (instead of doing the external drive) but it’s hard to know how much space the OS and whatever other stuff is needed takes. Do you happen to know how much free space she had when the full library was internal?

So now she keeps her videos on the external and photos on the internal and both can be backed up to time machine if you go into time machine settings and MINUS the external from the exclusion list (the first back up took forever though).
EDIT: The sammy gets hot. Put a fan on it while you're doing large amounts of copying.

Can you say more about keeping only videos on the external? Is there some way to automate that or is that manual?

Cool, didn’t know you could back up more than one drive via Time Machine - does the external drive just show up as another folder?

On heat, did you use the standard T7 or Touch or Shield?

 

[smoking monkey]

Mind if I ask why you went through this process with a 588GB library on a 1TB internal drive? Guessing she has other stuff taking up a lot of space. I don’t have much else taking up much space and trying to determine whether a 1TB internal drive may be enough (instead of doing the external drive) but it’s hard to know how much space the OS and whatever other stuff is needed takes. Do you happen to know how much free space she had when the full library was internal?

Her library is growing fast. And has almost doubled in the last 2 years. I thought I better get on top of it fast (there are also preventative ways as well that she's now working through to stop the proliferation!). I can't remember the exact amount of free space she had, but it was racing up as she has other stuff on there. I've always gone by the rule of leaving 10 percent of your HD free. So it's really a 900G drive and with the size of the OS etc., your space starts to become very finite very quickly when you're filling it up with photos and videos on a regular basis.

Can you say more about keeping only videos on the external? Is there some way to automate that or is that manual?

There isn't a way to automate it that I'm aware of, but there is a very simple way to delete all photos once they've been imported. In the top right area of Photos you can choose what to display in the library. Just choose photos then select them all and delete. Then go into the temp bin and delete them permanently. I think photos is set to a default 30 days perm delete. I don't want that temp bin getting filled up as it can cause trouble sometimes.

Cool, didn’t know you could back up more than one drive via Time Machine - does the external drive just show up as another folder?

Not sure how it shows up. I didn't actually look after the back up had finished. I will check when I get the chance and get back on that.

On heat, did you use the standard T7 or Touch or Shield?

It would just be the normal one.

 

[smoking monkey]

I don't remember exactly but maybe I already had the database on the drive and when I tried to open it it made a duplicate instead of just opening it. Not sure though. All I know that a 500+ database wouldn't fit on a 1 TB drive. It kept on saying I didn't have enough space until I switched to a 2 TB drive.

I imagine something went wonky during the set up process. I just followed steps I found on the net to do it and it worked fine.

 

[FFabian]

The SanDisk Extreme SSD is quite decent I hear. Make sure to get the one making 1000 MB/s.

 

[solouki]

Hi all,

Just as an example of a "working" case...and then my own personal "beef".

I use 55 Photos.app libraries (1.5TB) and 75 Music.app libraries (0.5TB) on an external 18TB HDD (150MB/s) without any problems. I even often connect to this external drive over 802.11ax WiFi from other machines. This HDD also has 12TB of data and 250GB of RSA (4096-bit) encrypted sensitive data on it. In fact, I have two of these, one serving as a backup of the other.

I change Music and Photos libraries often, without any issues, but I too hate the fact that the apps themselves do not indicate which library is currently open (if I have forgotten which library is open -- I use the Terminal commandline to determine which one).

So, although this HDD is fairly slow (150MB/s), it is fast enough for most uses. But when I require speed, say for editing a photo or audio file, I transfer the specific library (or usually the exported files) to a Samsung X5 SSD and then to the AS Mac's internal SSD. Once I have finished with the edits, I transfer the edited library (or edited files) back to the X5 SSD and then back to the 18TB HDDs. I use "rsync" to transfer the library/files so that only the modified versions are communicated. This also works well for me, especially when my own codes require certain data from the 12TB of data on the 18TB HDD.

Just so you know, the X5 SSD has transfer speeds of around 2.5GB/s while the AS Macs internal SSDs have transfer speeds of around 6.5GB/s. If one requires faster external SSD transfer speeds, then there is always iodyne.com Pro Data with transfer speeds of around 5GB/s by utilizing multiple Thunderbolt ports (the iodyne is quite expensive, but you can "roll" your own much cheaper).

Now for my pet peeves ... I dislike the fact that the latest versions of both the Music.app and the Photos.app have altered the names of the original media files. For instance, in the Photos.app the originals now have names like:

0BD36969-001F-4C2F-9446-127B8FEE63CF.nef
0BE47A90-5DCE-4886-8FF4-593A31A88C36.cr2

that is, a hash coded filename but luckily still the original file's extension. The actual original filenames are now stored in a database. Fortunately, when you export a file it looks up the original filename and exports the original filename with its proper extension. But I worry that a database corruption or new version of Photos.app will loose the original filenames.

The Music.app also has renamed the original media, and now the originals have their original filenames but they have been converted to .m4a extensions. I have both lossy and lossless originals, and both now have the same .m4a extensions with one or the other filename being modified by adding a "2" in order to distinguish them.

Because of these filename and extension renamings in the latest Music.app and Photos.app (older versions of iPhoto and iTunes kept the original filenames intact), I'm seriously thinking about abandoning the Music.app and Photos.app and using other third-party alternatives that do keep the original names of the original media files.

Solouki

 

[skyhawkmatthew]

I've been using a 1TB Samsung T5 for my ~700GB Photos library on my M1 iMac since I got it a bit over a year ago. It's been totally reliable and perfectly fast enough even editing RAW files and large panoramas, etc.

 

[acousticbiker]

Thanks, all, ended up going with a sale-priced Samsung T7 Shield.

Now does anyone have advice on the following question?

https://forums.macrumors.com/threads/shared-icloud-photos-library-on-mac-with-photos-library-on-ssd-and-two-users.2364461/