Linux Kernel in a Nutshell

Name

DISCONTIGMEM_MANUAL — Discontiguous memory

This option provides better support than flat memory for discontiguous memory systems. These systems have holes in their physical address spaces, and this option handles the holes more efficiently. However, the vast majority of hardware has quite flat address spaces, and can experience degraded performance from the extra overhead this option imposes.

Many NUMA configurations will have this as the only option.

If unsure, choose Flat Memory over this option.