Re: Removal of unexec support from glibc malloc

[Ken Raeburn]

> On Jan 18, 2016, at 20:59, Dmitry Gutov <address@hidden> wrote:
> 
> On 01/19/2016 04:44 AM, Ken Raeburn wrote:
> 
>> Try removing the after-load-functions hook in loadup.el that invokes GC, and 
>> the explicit GC calls.
> 
> That brings the loading time down to ~4.8 seconds.
> 
>> Also maybe bump up gc-cons-threshold by an order of magnitude.
> 
> And that doesn't seem any appreciable effect here.

Huh.  Disappointing.  When I was poking at CANNOT_DUMP startup time about a 
year ago, I seem to recall that these helped, but I don’t remember how much.  A 
couple other things though:

* Since you (presumably) didn’t configure with CANNOT_DUMP, temacs may still be 
making “pure” copies of objects.  But I just tried rebuilding with CANNOT_DUMP, 
and temacs aborted in bidi_initialize; I’m guessing it wants to use something 
initialized by Lisp code that hasn’t run yet.

* If you’re on a Mac, loading elisp is extra slow, thanks to getc() calling 
mutex functions that are very slow (at least compared to the glibc versions); I 
tried out a workaround using getc_unlocked, which seemed to help a lot.

Ken