Linux 6.8 To Drop The SLAB Allocator, SLUB Optimizations Coming Too

Following the SLOB allocator removal earlier this year, the Linux 6.8 kernel in the new year is now positioned to remove the SLAB allocator. Additionally, the lone good-for-everything SLUB allocator is set to receive further optimizations.

Linux 6.5 officially deprecated the SLAB allocator and with no one raising objections to its removal or expressing why they can't migrate to SLUB, Linux 6.8 is now slated to be the kernel removing SLAB.

Patches were posted in November for removing SLAB and those patches are now queued in slab.git's slab/for-next branch ahead of the Linux 6.8 merge window opening in a few weeks.

Dropping SLAB lightens the kernel load by around 5k lines of code and most important makes it easier to improve SLUB moving forward and having less maintenance by kernel developers.

Also queued in slab/for-next are patches for optimizing SLUB's free fast path code layout and alloc fast path code layout, among other optimizations.