Big Sur has an "OS Update" snapshot volume under the Big Sur volume. Do I need it?

The Update volume is a normal part of Big Sur.

Apple used to stage updates in /Library/Updates folder, but it now appears they have started staging in an APFS Volume, instead. There still is an Updates folder in Library, so it may be related to something else, perhaps OS updates as opposed to other updates.

I have no way of knowing, but I don't think they intended to show that in Disk Utility.

Here is an example. Please do not delete any volumes in the APFS Container.

/dev/disk0 (internal, physical):

   #:                       TYPE NAME                    SIZE       IDENTIFIER

   0:      GUID_partition_scheme                        *500.3 GB   disk0

   1:                        EFI ⁨EFI⁩                     314.6 MB   disk0s1

   2:                 Apple_APFS ⁨Container disk1⁩         500.0 GB   disk0s2

/dev/disk1 (synthesized):

   #:                       TYPE NAME                    SIZE       IDENTIFIER

   0:      APFS Container Scheme -                      +500.0 GB   disk1

                                 Physical Store disk0s2

   1:                APFS Volume ⁨Macintosh HD⁩            15.3 GB    disk1s1

   2:              APFS Snapshot ⁨com.apple.os.update-...⁩ 15.3 GB    disk1s1s1

   3:                APFS Volume ⁨Macintosh HD - Data⁩     252.4 GB   disk1s2

   4:                APFS Volume ⁨Preboot⁩                 474.0 MB   disk1s3

   5:                APFS Volume ⁨Recovery⁩                610.8 MB   disk1s4

   6:                APFS Volume ⁨VM⁩                      1.1 GB     disk1s5

If you need more details, see https://eclecticlight.co/2020/09/16/boot-volume-layout/ as reference.

Hi,

I also have the same question, I was baffled once I saw that 10% of my available disk space is blocked by this snapshot. The problem is I cannot delete it in disk utility. Anyone has an idea how to delete this volume? Or will this be un-blocked automatically at some point?

Regards,

Robert

Is this volume has something to do with the excessive and large "Others" file volume in Storage management view?

I was wondering why I have so much space taken from my SSD in my unused brand new M1 MBP when I suddenly jumped into disk utility and find out that there is a com.apple.os sharing the entire SSD volume with Macintosh HD.

Makes kinda sense a secured copy of the OS plus cache and apps temp files so far kinda makes up to the space taken by "other", since CleanMyMacX could exactly detect everything.

When it comes time to install a major macOS update, Big Sur loads up a separate snapshot of your system volume in the same APFS container as your system and data volumes (this volume is a persistent hidden volume called “Update,”

https://arstechnica.com/gadgets/2020/11/macos-11-0-big-sur-the-ars-technica-review/11/#h3

The System Volume now stores the OS as a snapshot, maybe there are several, one of which is in use, for the current build.

How large is your Macintosh HD (not Macintosh HD - Data)?