d84d2909c3
Detect whether chunks start off as THP-capable by default (according to the state of /sys/kernel/mm/transparent_hugepage/enabled), and use this as the basis for whether to call pages_nohuge() once per chunk during first purge of any of the chunk's page runs. Add the --disable-thp configure option, as well as the the opt.thp mallctl. This resolves #541.