Condition

  • GNU Emacs 27.1 (build 1, x86_64-pc-linux-gnu, GTK+ Version 3.24.24, cairo version 1.16.0) of 2023-02-23, modified by Debian

  • Loaded packages

    (custom-set-variables
 '(package-selected-packages
   '(gnuplot helm-org clang-format org use-package ox-gfm ac-helm edit-indirect org-ref ac-ispell org-latex-impatient ac-math electric-cursor yasnippet auto-complete-auctex auto-complete zotxt zotelo auctex cmake-font-lock cmake-mode flycheck maxima flycheck-plantuml plantuml-mode tabbar session pod-mode markdown-mode magit initsplit htmlize graphviz-dot-mode folding eproject diminish csv-mode browse-kill-ring boxquote bm bar-cursor)))

Phenomenon

If I intermittently use Emacs without closing it for hours, its memory consumption can be as high as 8 GB. I tend claim this indicates a memory leak. However, which loaded package is the culprit is still unknown. I guess the suspects might be helm and auto-complete related packages.

Remedy

I’ve tried executing garbage-collect, which has no effect

Next, I’ve disabled the following packages to see if this high memory consumption can be relieved or removed.

Disabled packages which have been removed from the variable package-selected-packages:

  • helm-org
  • ac-helm
  • ac-math
  • auto-complete-auctex
  • auto-complete

Meanwhile, I run through the initialization script ~/.emacs and comment out any unnecessary package requirements and configurations. Especially, the following lines of helm initialization code are commented out.

(require 'helm-config)
(helm-mode 1)
(define-key global-map [remap find-file] 'helm-find-files)
(define-key global-map [remap occur] 'helm-occur)
(define-key global-map [remap list-buffers] 'helm-buffers-list)
(define-key global-map [remap dabbrev-expand] 'helm-dabbrev)
(define-key global-map [remap execute-extended-command] 'helm-M-x)
(unless (boundp 'completion-in-region-function)
  (define-key lisp-interaction-mode-map [remap completion-at-point] 'helm-lisp-completion-at-point)
  (define-key emacs-lisp-mode-map       [remap completion-at-point] 'helm-lisp-completion-at-point))

(global-set-key (kbd "M-x") 'helm-M-x)

After doing the above and restarting Emacs with previous desktop loaded, the initial memory consumption is 74 MB. Running Emacs for hours, the memory consumption only increases to 200 MB.

Lessons learned

  • Only load those frequently used packages to reduce the probability of being confronted with errors and bugs, which are either caused by a specific package or by the symbiotic effect of some packages.
  • It is worthy and rewarding to be patient to monitor and tune the behavior of our production tool.