Recently, erofs-utils has supported multi-threaded `-Efragments`.

The mkfs performance of `-Efragments` is greatly improved, therefore users don't need to use `-Eall-fragments,fragdedupe=inode` as a workaround since `-Eall-fragments` will make the entire inodes as fragments which can impact runtime performance although the image sizes out of `-Eall-fragments` are a bit smaller (in principle, fragments should only be applied to the remaining tail parts or small files).

More details, also see: https://erofs.docs.kernel.org/en/latest/mkfs.html

Currently Fedora already has erofs-utils 1.8.10 package, and Fedora KIWI already switches to this mode for FL43: https://pagure.io/fedora-kiwi-descriptions/pull-request/183

EL10 based CoreOS also would like to bump up erofs-utils version to use `-Efragments`: https://github.com/coreos/fedora-coreos-tracker/issues/1991#issuecomment-3134658245

To test `-Efragments`, just use erofs-utils testsuite and:

`# MKFS_OPTIONS="-Efragments" make check`