[$] Improving control over transparent huge page use

The use of huge pages can significantly increase the performance of many
workloads by reducing both memory-management overhead in the kernel and
pressure on the system's translation lookaside buffer (TLB). The addition
of transparent huge pages (THP) for the 2.6.38 kernel release in 2011
caused the kernel to allocate huge pages automatically to make their
benefits available to all workloads without any effort needed on the
user-space side. But it turns out that use of huge pages can make some
workloads slower as the result of internal memory fragmentation, so the THP
feature is often disabled. Two patch sets aimed at better targeting the
use of transparent huge pages are currently working their way through the
review process.