When migrating a MacBook from HDD to SSD, I did a block-level copy using
dd. Because the SSD already contained a different OS image from a previous test, I believe for optimal performance, it would be the best to issue a TRIM for every unused block in the new filesystem to inform the SSD controller. Is it possible to TRIM the free space manually for an AFPS volume on macOS (like FreeBSD’s
trim or Linux’s
I’ve read that macOS’s
fsck has a TRIM pass, so TRIM can be triggered manually by running
fsck -fy in single-user mode. But I didn’t see any message about TRIM when I tried it, so I guess it’s only applicable to HFS+ filesystems.