Log Message:
Import jemalloc-4.04, packaged for wip by Jonathan Buschmann
<jonthn+pkgsrc@pinacea.com>.

jemalloc is a general purpose malloc(3) implementation that emphasizes
fragmentation avoidance and scalable concurrency support.

jemalloc first came into use as the FreeBSD libc allocator in 2005.
In 2010 jemalloc development efforts broadened to include developer
support features such as heap profiling, Valgrind integration, and
extensive monitoring/tuning hooks.  Ongoing development efforts trend
toward making jemalloc among the best allocators for a broad range of
demanding applications, and eliminating/mitigating weaknesses that
have practical repercussions for real world applications.

This is a newer version of jemalloc than the one in NetBSD's libc.