APFS Formatting and Partitioning

[honestone33]

I have a Samsung 860 EVO 500 gig SSD installed inside a nice, slim Orico enclosure, and I am very pleased with it. I just did another Catalina download, installation, migration of files, folders, settings, etc. from my (Mojave) late 2012 Mac Mini, and except for a couple of questions I have about that (will post another thread about that), everything went fine. But I have a question regarding Partitioning and APFS.

I began this latest "project" by first using Disk Utility (the Mojave version) to Erase and Format that Samsung 860 EVO 500 gig SSD as APFS. Went smooth, as expected. I then clicked on the Partition Tab in Disk Utility, and the following dialogue came up:

"Apple File System Space Sharing

APFS volumes share storage space within a container, occupying a single partition. Adding and deleting APFS volumes is faster and simpler than editing a partition map.

To add a new volume to a container without seeing this message, use the Add APFS Volume command in the Edit menu or the Add/Delete Volume toolbar item.

Would you like to add a volume to the container, or partition the device?"

I had never seen that before, so I took the "easy" way out and chose to Add another APFS Volume. That completed successfully, and after renaming the two volumes as "Catalina Test" and "Test Volume", I can see that each of them has a capacity of 500 Gig. So, I assume that means those two volumes will share the 500 gig of space on the SSD.

Is this a wise choice, or should I have just Partitioned the SSD "normally"? What are the advantages and disadvantages of that "Volume Sharing" of space?

 

[Fishrrman]

I wanted actual "partitions" when I set up my 2018 Mini.

And I also wanted HFS+ (NOT APFS) on most of those partitions.

So... here's how I did it:
1. Booted from an external source
2. Used disk utility to create 4 HFS+ partitions
3. Used disk utility to "convert to APFS" the first partition
4. Remaining 3 were left as HFS+
5. Installed OS Mojave to APFS partition
6. Installed various data to other (HFS+) partitions.

Works well enough for me.

BE AWARE:
Before you can even boot externally on a t2 Mac, you must first boot to the recovery partition, then open "Startup Security", and then DISABLE its features to permit booting from external volumes.

 

[honestone33]

I wanted actual "partitions" when I set up my 2018 Mini.

And I also wanted HFS+ (NOT APFS) on most of those partitions.

So... here's how I did it:
1. Booted from an external source
2. Used disk utility to create 4 HFS+ partitions
3. Used disk utility to "convert to APFS" the first partition
4. Remaining 3 were left as HFS+
5. Installed OS Mojave to APFS partition
6. Installed various data to other (HFS+) partitions.

Works well enough for me.

BE AWARE:
Before you can even boot externally on a t2 Mac, you must first boot to the recovery partition, then open "Startup Security", and then DISABLE its features to permit booting from external volumes.

Thanks for the reply. I actually have 2 other external Samsung 850 Pro 512 gig SSDs, each containing 3 APFS partitions. I use 2 of them for SuperDuper! backups for each of my Macs, and the third one for storing "miscellaneous" files (mainly TV series and some movies). From what I remember, I partitioned them, via Disk Utility, like "normal", but choosing APFS for the format for each partition.

For now, the only use I would have for HFS+ format is for pugging in a device, via USB, to either of our Roku Ultra Streaming devices. Apparently, the Roku software cannot recognize APFS format. But I have some USB 3.0 Flash Drives that I can use for such purposes.