How to obtain and read entries in the Unified log made by APFS. Their structure, and a guide to their identification and occurrence.
Space Manager
From the GPT division of storage space, through APFS containers, down to individual volumes, an account of how APFS works.
Enabling the TRIM command was once thought important to maintain good write performance on SSDs. What has happened to it? Should we still be enabling it?
Disk structure diagrammed for comparison, from the partition table, to HFS+ and APFS volumes, with further references.
What you need to know about the APFS file system, its containers and volumes, so you can understand errors and how to repair them.
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