Removing support for Emacs unexec from Glibc

Posted Feb 16, 2016 20:34 UTC (Tue) by fw (subscriber, #26023)
Parent article: Removing support for Emacs unexec from Glibc

Minor correction: Almost all of the load time increase in an undumped Emacs comes from the way string allocation works in this mode: It performs a linear search over the heap to determine if the requested string has been allocated before and there is an allocation which can be reused (so it does string interning, like Lua, but without a hash table). Once you disable that, load time goes down to a more bearable 0.4 second (on my nearly four-year-old laptop).

I mentioned this in the emacs-devel thread, but it was pretty out of control at that point.

Removing support for Emacs unexec from Glibc

Posted Feb 17, 2016 17:32 UTC (Wed) by nye (subscriber, #51576) [Link]

>Almost all of the load time increase in an undumped Emacs comes from the way string allocation works in this mode: It performs a linear search over the heap to determine if the requested string has been allocated before and there is an allocation which can be reused (so it does string interning, like Lua, but without a hash table)

That's... disgusting. I remember doing something similarly nasty in, like, my second C program ever, and being pretty ashamed about it.