const MALLOC_CONF_METADATA_THP: &str;Expand description
Asks jemalloc to back allocator metadata with huge pages where it can.
Jemalloc needs MADV_HUGEPAGE (which its build ignores on 32-bit ARM) or
memcntl. Without either, a debug build aborts during allocator
initialization, and the key’s only remaining effect in release is
whether the tcache stacks come from the never-purging base allocator,
since base blocks keep the 2 MiB alignment and rounding of
BASE_BLOCK_MIN_ALIGN either way.