bug#37321: 27.0.50; Excessive gc in a use case (el-search)

[Michael Heerdegen]

Hi,

apparently due to the latest changes in gc (I noticed the problem today,
after doing a make bootstrap yesterday), el-searching is slowed down by
a factor of 10000 or so.  Profiling shows that nearly all of the time is
spent in gc.

To reproduce from emacs -Q:

M-x list-packages
Install el-search
M-x el-search-emacs-elisp-sources 'pcase M-RET

This will start an el-occur for the symbol 'pcase in the Emacs Elisp
sources.  This normally takes around 10 seconds but is now just
unusable.

(If you want me to bisect, do I have to make bootstrap, or does a simple
make suffice?)

Hope someone can help.

TIA,

Michael.





In GNU Emacs 27.0.50 (build 2, x86_64-pc-linux-gnu, GTK+ Version 3.24.10)
 of 2019-09-06 built on drachen
Repository revision: 459b416e5f950c6127f10c9eca68d65bdab688d4
Repository branch: master
Windowing system distributor 'The X.Org Foundation', version 11.0.12004000
System Description: Debian GNU/Linux bullseye/sid