Сабж. Как известно, этот выбор у юзеров появился в ядре 4.14.
Разница, напоминаю, такова:
FRAME_POINTER_UNWINDER
...
The unwinder itself is fast and it uses less RAM than the ORC unwinder, but the kernel text size will grow by
~3% and the kernel's overall performance will degrade by roughly 5-10%.
This option is recommended if you want to use the livepatch consistency model, as this is currently the only
way to get a reliable stack trace (HAVE_RELIABLE_STACKTRACE).
ORC_UNWINDER
...
This option enables the ORC (Oops Rewind Capability) unwinder for unwinding kernel stack traces. It uses a
custom data format which is a simplified version of the DWARF Call Frame Information standard.
This unwinder is more accurate across interrupt entry frames than the frame pointer unwinder. It also enables a
5-10% performance improvement across the entire kernel compared to frame pointers.
Enabling this option will increase the kernel's runtime memory usage by roughly 2-4MB, depending on your kernel
config.
