Description of APFS layout?

Question

Hello;I am trying to look at the structure of an APFS volume.  In my example I have a 120GB SSD drive with an APFS volume.  Which is listed here:Question:  Whate is Apple_KernelCoreDump?#:                       TYPE NAME                    SIZE       IDENTIFIER   0:      GUID_partition_scheme                        *115.0 GB   disk0   1:                        EFI EFI                     209.7 MB   disk0s1   2:                 Apple_APFS Container disk2         114.2 GB   disk0s2   3:       Apple_KernelCoreDump                         655.4 MB   disk0s3Viewing the volume or the syntensized volume:/dev/disk2 (synthesized):   #:                       TYPE NAME                    SIZE       IDENTIFIER   0:      APFS Container Scheme -                      +114.2 GB   disk2                                 Physical Store disk0s2   1:                APFS Volume DEVELOPER               10.7 GB    disk2s1   2:                APFS Volume Preboot                 19.7 MB    disk2s2   3:                APFS Volume Recovery                518.9 MB   disk2s3   4:                APFS Volume VM                      824.0 MB   disk2s4What is Preboot and VM?Bruce

grahamperrin · Answer

Apple_KernelCoreDumpTechnical Note TN2118: Kernel Core Dumps is, or will be, outdated but essentially, core dumps:&amp;gt; … allow you to examine the state of the kernel after a kernel panic or hang. …A dump may contain sensitive data.PrebootIf the startup volume (boot volume) is locked – think FileVault – then the preboot volume should be used to present the dialogue that prompts the user to enter the passphrase for their account or (in some cases) the passphrase for Disk Password.I&#x27;ll post more about preboot compatibility elsewhere. In the meantime, you can use Terminal to learn a little about the udpate routine for preboot volumes. Enter:diskutil apfs updatePrebootVM/var/vmtraditionally uses the HFS Plus file system to store swap files and – for any Mac that hibernates – a sleepimage file.Kernel Programming Guide: Memory and Virtual MemoryWith APFS, there&#x27;s a separate volume for virtual memory. Expect the volume to be mounted at /var/vm

truenorthbruce · Answer

Perfect thanks...just found the TN2118! Appreciate the response.

Description of APFS layout?

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