Settings for minimal HDD usage on main computer?

I’ve been reading forum messages for the last few days, but I’m still confused about the best way to use Mylio for my scenario.

I’ve got about 100K photos spread out across: multiple folders on a NAS, the Apple Photos folder on my iMac, and others on Google Photos. I’d like to:

  1. Use an external 8TB USB drive (attached to my iMac) as the main vault.
  2. Use almost none (or as little as possible) of the space on my iMac internal drive.
  3. Keep the original versions of all photos where they are now, and simply have a copy of everything on the external USB to quickly find photos based on faces, dates, etc.

I thought I understood how to do this, but Mylio keeps copying all my source photos to the “Mylio Pictures” directory that it created on my iMac.

How can I get this right??

I wanted to keep everything where it was at first but once i gave in and put everything inside the Mylio folder, it just got so much easier. I have two external drives as vaults and set my macbook pro to auto-optimized. I download originals to my computer as needed and clear the cache when that need is over. The external drives always have the originals when i need it.

Couldn’t you just move the Mylio library folder from your internal drive to the external USB drive?
Troubleshooting: Moving the Location of Your Mylio Library - Mylio Support

I suppose that’s one way, but then it wouldn’t make sense for the external USB drive to be a vault as well, right? So would I still need a vault somewhere else?

Well, this way would meet your criteria #2 - “Use almost none (or as little as possible) of the space on my iMac internal drive”. Not even Thumbnails would be stored on the internal drive.

EDIT: the external drive could still be a “Vault”, even though it happens to be your main Mylio library device. “Vault” simply means it contains a COMPLETE copy of all your Mylio photo files. Yes, you may need ANOTHER Vault if you want everything protected against drive failure.

Ok, thanks! I’m still a bit confused on the difference between the library folder and a vault folder. But it seems that the library folder is only meant to be temporary storage? I see that I can clear my cache, which (I think) would clear the files in my library folder (but not the vault).

I’m not sure what benefit would come from having both the library folder and the vault on the USB, especially if I keep another vault somewhere else.

This is where Mylio’s choice of terminology is confusing. “Vault” implies “safely backed up” - but that’s not necessarily the case. “Vault” really just means a COMPLETE SET of your photo files. A “Vault” may actually be a mix of original master files that exist nowhere else, plus synced backup copies of originals from other devices. But altogether it’s a “complete set” of your photos.

So, assuming I never clear my cache, wouldn’t the library folder also be a complete set of photo files?

If your computer’s Mylio Library folder has sufficient space to be a Vault, there’s no “cache”. By definition a Vault contains everything, permanently. No temporary caching.

If your Library folder doesn’t have sufficient disk space to be a Vault (complete copy) then yes, it’s a Thumbnails-only device, with options to sync or cache some subset of Previews and/or Originals as space allows.

A computer’s Mylio library folder can certainly be a Vault, if there is sufficient disk space. For most laptops with small internal drives this won’t be an option. But for example - my primary Mylio machine is a desktop workstation with internal 48TB drive array. It has more than enough space to be a “Vault”. And so it is both a “Vault” and my primary Mylio library folder.

One further note: in order to use my suggestion - to move your computer’s Mylio library folder to the external drive - you’d want to be sure that external USB drive is more or less “permanently” plugged into your laptop.

If that external drive is likely to be disconnected/connected then it’s best to leave your Mylio library folder on the internal drive (either Thumbnails-only or an Auto-Optimized mixture of thumbs/previews), and set up the external drive as a Vault. This way Mylio can at least see the Thumbnails if the external drive is disconnected.

So, after playing around some more, it seems best to keep the library on the main HDD, but set as “Thumbnails”. It took me some time to figure out the the underlined box on the “Sync Policy Settings” screen under “Device Quality” was the setting. It would have been clearer to make this a pull down menu, as I thought the box controlled the dialog being shown underneath.

Yeah, it’s kind of an inscrutable dialog box, which has changed a lot over the years. I remember it took me a long time to figure out “Show Customizations” and realize the [P] and [O] tabs there let you explicitly control the mixture of [P]reviews and [O]riginals to sync to this device - eg, as an alternative to Auto-Optimized. I use that feature on my iPhone & iPad to sync Previews for all my 3-star & higher photos (the ones I might want to actually show somebody).

Hopefully the powers-that-be at Mylio take a look at these messages, and consider them in the next UI upgrade!

I’ve tried using a minimal setup on my computer’s main drive, and it worked, but with the occasional annoyance that while browsing, the image begins as a thumbnail, then becomes a preview that has just been fetched - depending on the speed of your drives, you might notice that. The other thing is that in order to duplicate, export or print full-size images, you have to tell Mylio to cache the original - it won’t do it automatically - and then later, clear the cache - it won’t do that automatically either. I decided to sync all previews locally to speed up browsing, and I am putting up with the ‘get original’ issue.

Does keeping the previews take up considerably more space than just the thumbnails?

It does take more space - previews seem to have 2048 pixels on the longer side. You can set the overall sync policy to thumbnails then override that folder by folder, so that only the images you are working on have local previews - see for more.

Update: Looks like my recent thumbnails are around 30kb each, while previews are generally 600-900kb each.