Overview of clone files, dataless files, sparse files, symbolic links, and firmlinks, and how used and free space is accounted for in APFS.
TRIM
This has become more complex with increasingly popular hybrid drives that support USB4/Thunderbolt and fall back to USB 3.x.
Check its protocol support and expected maximum transfer rate, then whether it supports SMART indicators and Trims with APFS. Finally check its real-world performance.
Given that Thunderbolt SSDs are unusual and expensive, should you buy a USB4 model that claims to be compatible with Thunderbolt? Watch out for the traps.
If you want it to have full TRIM and SMART support, it’ll need to have an NVMe interface and a Thunderbolt connection.
There’s a big difference between the storage that’s available, and what’s advisable. Whether it’s affordable is another question.
Why should you trim an SSD? How to tell whether an SSD needs trimming, finding out whether it has trim support, and whether it does trim.
A step-by-step account of how Disk Arbitration and APFS mount an external disk, from handling its partitions, to performing trims.
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?
Traced from recognition of the cable connection, through establishing PCI streams, to mounting the volume with APFS, and the bonus of a good trim at the end.