I tried to include nedmalloc 1.0.5 in the benchmark, but it quite simply isn't polished enough for actual use. To start with I had to remove an invalid assertion in malloc() and implement posix_memalign(), only to find that it crashes within moments of application startup.

It is not a performance evaluation, but there is a comment from Niall (the author of nedmalloc) in Jason Evans' blog that might give you a hint.

http://t-t-travails.blogspot.com/2010/04/red-black-trees-rev...