Re: emacs empty startup time increased from v 27.1 to 29.0 by factor 3?

[Eli Zaretskii]

> From: Gregor Zattler <telegraph@gmx.net>
> Date: Mon, 23 Jan 2023 15:08:15 +0100
> 
> time /usr/bin/emacs-gtk -Q -nw -f save-buffers-kill-emacs
> 
> which starts emacs 27.1 as precompiled in debian / Bullseye
> and kills it again, a low time values on my laptop are e.g.:
> 
> real    0m0,328s
> user    0m0,262s
> sys     0m0,058s
> 
> 
> while for emacs v29.0 the same command line achives low
> values like this one:
> 
> real    0m1,007s
> user    0m0,847s
> sys     0m0,154s
> 
> The 29.0 version is compiled with native-compilation
> support.  Does this explain the differences?

It could.  Emacs with native-compilation needs to load all the
preloaded Lisp packages as shared libraries, as opposed to just
mapping the pdumper file into the address space in Emacs 27.  To be
sure, build Emacs 29 without native-compilation, and then compare.