Comment by toast0

It is on FreeBSD. :P Change your malloc, change your life? May as well change your libc while you're there and use FreeBSD libc too, and that'll be easier if you also adopt the FreeBSD kernel.

I will say, the Facebook people were very excited to share jemalloc with us when they acquired my employer, but we were using FreeBSD so we already had it and thought it was normal. :)