All APFS volumes in a single partition/container share its free space. How can that be measured? How much could be purged, and how do special file types affect it?
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To work out how long you’ll be able to use your present backup storage, you need to know how much space is free now, and the rate at which free space is being used by further backups. This app can forecast that, and more.
How to resolve an inode number to a path and filename, and how to go the other way from a file to an inode number. How you can tell which files are on System and Data volumes.
Add another volume to your Mac’s internal SSD and try to eject it. All hell breaks loose as the Finder wants to eject the whole disk, it seems. Probably a 6-year old bug.
Everything you need to know about Containers, Group Containers and Daemon Containers, providing a sandboxed Home folder for apps.
How to obtain and read entries in the Unified log made by APFS. Their structure, and a guide to their identification and occurrence.
Keybags, wrapping keys, VEKs and KEKs all explained. Did you realise how Recovery Keys are implemented? Or how the SSV protects against read errors?
From the GPT division of storage space, through APFS containers, down to individual volumes, an account of how APFS works.
A step-by-step account of how Disk Arbitration and APFS mount an external disk, from handling its partitions, to performing trims.
How APFS containers and volumes work. What hard links, clones and sparse files are, and when they break down.
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