Re: Building the web site is slow

[pelzflorian (Florian Pelz)]

On Mon, Nov 23, 2020 at 04:03:26PM +0100, Ludovic Courtès wrote:
> Do you think we could arrange
> to build all the languages in a single ‘haunt build’ run, would that
> help?

What kept me from doing a single `haunt build` run are two things.
The lesser is that, when not using .guix.scm, running `haunt build`
builds only the current locale when testing, which is quick.  Only
when building all languages via .guix.scm it becomes slow.

But the real reason for using multiple haunt invocations
is that the website i18n runs as a macro when
loading a Scheme file.  That is, if a Scheme file contains

(G_ `(a (@ (href ,(guix-url "contribute/"))) "Git repositories"))

then the G_ macro will use gettext with the currently set locale to
change it to, for example

`(a (@ (href ,(guix-url "contribute/"))) "repositorios Git")

All this runs at macro expansion time before procedure calls like
guix-url unlike regular gettext.  That is, it runs when Haunt first
processes the G_.  If the same invocation of Haunt is to process the
G_ for multiple translations, it would somehow have to unload and
macro expand the code a second time.

Anyway, I am not sure the `haunt build` runs are the culprit.  If it
is a problem with spinning disks only, maybe .guix.scm can be made to
copy less from the same disk to the same disk but copy more from disk
to a file system in RAM and from a file system in RAM to disk.


> I haven’t tried profiling yet, but I can take a look.
> 
> Ludo’.

It is funny, when I try to profile via

cd ~/src/guix-artwork/website
guix install -p haunt-profile guile-syntax-highlight guile-commonmark haunt
LC_ALL=en_US.utf8 \
 GUILE_LOAD_PATH=haunt-profile/share/guile/site/3.0:$GUILE_LOAD_PATH \
 /gnu/store/18hp7flyb3yid3yp49i6qcdq0sbi5l1n-guile-3.0.2/bin/guile
scheme@(guile-user)> ,profile ((@ (haunt ui) haunt-main) "haunt" "build")

it crashes, but only when using ,profile.  I will investigate
tomorrow.

Regards,
Florian