A simple benchmark testing the performance of the activation of the
hundreds of Emacs packages was then run using:

--8<---------------cut here---------------start------------->8---
$ ./pre-inst-env guix environment --pure -m emacs-packages-manifest.scm \
                                  --ad-hoc emacs
[env]$ /run/setuid-programs/sudo /bin/sh -c 'echo 3 > /proc/sys/vm/drop_caches'
[env]$ emacs --batch --no-site-file \
    --eval="(progn (require 'guix-emacs) \
                   (require 'benchmark) \
                   (message \"(total gc-count gc-time) = %s\" \
                            (benchmark-run 1 (guix-emacs-autoload-packages))))"
--8<---------------cut here---------------end--------------->8---

On the master branch:

--8<---------------cut here---------------start------------->8---
[...]
Loading /gnu/store/qajc70c7nqycs1301ram8s3x7k9ibg5f-profile/share/emacs/site-lisp/zotxt-autoloads...
Loading /gnu/store/qajc70c7nqycs1301ram8s3x7k9ibg5f-profile/share/emacs/site-lisp/zoutline-autoloads...
Loading /gnu/store/qajc70c7nqycs1301ram8s3x7k9ibg5f-profile/share/emacs/site-lisp/ztree-autoloads...
(total gc-count gc-time) = (25.242400751 13 0.189669369)
--8<---------------cut here---------------end--------------->8---

Or about 0.65 s on a warm cache.

On a branch with these changes:

--8<---------------cut here---------------start------------->8---
Error loading autoloads: (file-missing Cannot open load file No such file or directory kotl/kotl-autoloads)
Error loading autoloads: (file-missing Cannot open load file No such file or directory helm-easymenu)
Error loading autoloads: (file-missing Cannot open load file No such file or directory /gnu/store/ryh0rasi9frm98dkd3kbck6hya6hn2qr-profile/share/emacs/site-lisp/guix/flycheck-cpplint-0.1-1.1d8a090/flycheck-cpplint-autoloads)
Error loading autoloads: (file-missing Cannot open load file No such file or directory /gnu/store/ryh0rasi9frm98dkd3kbck6hya6hn2qr-profile/share/emacs/site-lisp/guix/evil-anzu-0.03/evil-anzu-autoloads)
Error loading autoloads: (file-missing Cannot open load file No such file or directory /gnu/store/ryh0rasi9frm98dkd3kbck6hya6hn2qr-profile/share/emacs/site-lisp/guix/erc-image-0-3.82fb387/erc-image-autoloads)
ad-handle-definition: `ido-completing-read' got redefined
Error loading autoloads: (file-missing Cannot open load file No such file or directory tex-site)
(total gc-count gc-time) = (26.175704339 47 0.783184412)
--8<---------------cut here---------------end--------------->8---

Or about 3 seconds on a warm cache.

There a 6 errors that would need to be looked into, but I these look
like actual packaging problems rather than new issues.  The previously
used way to load the autoloads, '(load f 'noerror)' would have masked
them.

Thanks,

Maxim