APFS creates VM disk?

[LK LAW]

What is the purpose of this?

[doublepost=1498815412][/doublepost]Any idea what the PreBoot partition is for?

 

[Ritsuka]

APFS can share space between partitions. So there is no downside in making a stand alone VM partition.

 

[LK LAW]

APFS can share space between partitions. So there is no downside in making a stand alone VM partition.

No but what are these partitions used for? And how does it defer from what HFS used to be?

 

[Ritsuka]

VM is for the swap. If your apps requires more RAM than the one you have it will use the space in the VM partition. HFS+ had one or more swap file instead.

 

[LK LAW]

VM is for the swap. If your apps requires more RAM than the one you have it will use the space in the VM partition. HFS+ had one or more swap file instead.

Didn’t Ubuntu Just ditch the swap ditch the swap partition instead in favor of swap files?

Also got any idea what the preboot partition does?

 

[aldrinjtauro]

Didn’t Ubuntu Just ditch the swap ditch the swap partition instead in favor of swap files?

Also got any idea what the preboot partition does?

Well, I don't think Ubuntu's system would work the way APFS does with volume space sharing. I think an Ubuntu swap partition would remove that space from availability irreversibly.

No idea what pre-boot is.

 

[grahamperrin]

… HFS+ had one or more swap file instead.

The same with APFS. Swap files.

… what the preboot partition does?

I answered a similar question in Apple Developer Forums. In a Terminal window:

diskutil apfs updatePreboot

 

[msephton]

I answered a similar question in Apple Developer Forums. In a Terminal window:

diskutil apfs updatePreboot

That doesn't answer what the reboot partition does. Rather it shows one thing you can do to it.

As I understand it, the reboot partition does some pre-boot housekeeping and security tasks, then hands off to the main boot partition.

 

[cmaier]

VM = virtual memory.

 

[grahamperrin]

Apple should update its developer document, The Early Boot Process …

 

[curnalpanic]

The same with APFS. Swap files.

Yes, there are still swap files, but the mount command reveals that the VM partition is mounted at /private/var/vm.