[$] Minimizing the use of tail pages
Compound pages are created by the kernel as
a way of combining a number of small pages into a single, larger unit.
Such pages are implemented as a single "head page" at the beginning,
followed by a number of "tail pages". Matthew Wilcox has concluded that
it would be beneficial to minimize the use of tail pages in the kernel; he
ran a session during the memory-management track at the 2019 Linux Storage,
Filesystem, and Memory-Management Summit to explore how that could be done.
The discussion ranged widely, veering into the representation of DMA I/O
operations, but few hard conclusions were reached.