[erlang-questions] Why is hybrid heap gone in R15B02?

[Xiao Jia]

According to http://www.erlang.org/download/otp_src_R15B02.readme:

   OTP-10105  Remove all code, documentation, options and diagnostic
     functions which were related to the experimental hybrid heap
     implementation.

I consider hybrid heap as a promising feature. Why is it removed?

Thanks,
Xiao Jia