4 ms·

I just disable emacs garbage collection entirely. Fast startup, no more random pauses, haven't noticed any problems yet. (This was probably like a year ago.) (

by dilap 4y ago

I just disable emacs garbage collection entirely. Fast startup, no more random pauses, haven't noticed any problems yet. (This was probably like a year ago.) (On the other hand, emacs is never quite problem free, so maybe this is introducing problems and I just haven't noticed.) I have tons of customizations and lots of packages, but be as religious as reasonable about lazy loading. $ time emacs --eval '(save-buffers-kill-emacs)' real 0.21s Not bad, but still very noticable, which is annoying. About half of it is unavoidable. $ time emacs -q --eval '(save-buffers-kill-emacs)' real 0.11s (-q disables reading the config file.) (With default GC settings, startup is about 300ms.)

matthews2 4y ago
Instead of totally killing the garbage collector, you can effectively turn it off during startup by setting gc-cons-threshold to a large number, and then restore it after init. The article touches on this but they don't increase it very much and restore it at the end of init.el (emacs-startup-hook runs later). early-init.el: (setq gc-cons-threshold most-positive-fixnum) (add-hook 'emacs-startup-hook (lambda () (setq gc-cons-threshold (* 2 1024 1024))))
- dilap 4y ago
  It was subtle in my message, but my other reason for disabling was to avoid random collection pauses when using emacs. A sibling poster recommended GCing on deactivate, which is an interesting idea! But again, I truly haven't been able to notice any ill effects of not GCing. I tend to probably leave emacs open for maybe a few hours at a time, so I guess in that sense I'm manually GCing. :-)
  - matthews2 4y ago
    Not running the GC at all is certainly interesting though :) Have you tried running 'M-x memory-report' before quitting to see how much memory you ended up using?
    - dilap 4y ago
      My emacs ain't new enough to have memory-report. I tried just running memory-report.el from HEAD, but it errored out (after hanging emacs for like 3 mins!). Anyway, here's the poor man's version: cons-cells-consed is 38315202 There's probably some roughly accurate map from that to number of bytes of memory allocated, I will take a totally random guess it's 10, which would give 383MB of memory used. I'm at half a day of usage, so figure 800MB by end of day. 16GB machine, so you can see why my "garbage collect once a day before bed" strategy is working out ;-). (Plus also I wonder how much of the uncollected garbage just gets paged out by the OS and never touched again.)
thom 4y ago
I like to do this to ensure GC happens occasionally, when I focus away from Emacs: (add-function :after after-focus-change-function (lambda () (unless (frame-focus-state) (garbage-collect))))
- dilap 4y ago
  Ah, neat idea! Thanks!

by dilap 4y ago

matthews2 4y ago

Instead of totally killing the garbage collector, you can effectively turn it off during startup by setting gc-cons-threshold to a large number, and then restore it after init. The article touches on this but they don't increase it very much and restore it at the end of init.el (emacs-startup-hook runs later). early-init.el: (setq gc-cons-threshold most-positive-fixnum) (add-hook 'emacs-startup-hook (lambda () (setq gc-cons-threshold (* 2 1024 1024))))

dilap 4y ago
It was subtle in my message, but my other reason for disabling was to avoid random collection pauses when using emacs. A sibling poster recommended GCing on deactivate, which is an interesting idea! But again, I truly haven't been able to notice any ill effects of not GCing. I tend to probably leave emacs open for maybe a few hours at a time, so I guess in that sense I'm manually GCing. :-)
- matthews2 4y ago
  Not running the GC at all is certainly interesting though :) Have you tried running 'M-x memory-report' before quitting to see how much memory you ended up using?
  - dilap 4y ago
    My emacs ain't new enough to have memory-report. I tried just running memory-report.el from HEAD, but it errored out (after hanging emacs for like 3 mins!). Anyway, here's the poor man's version: cons-cells-consed is 38315202 There's probably some roughly accurate map from that to number of bytes of memory allocated, I will take a totally random guess it's 10, which would give 383MB of memory used. I'm at half a day of usage, so figure 800MB by end of day. 16GB machine, so you can see why my "garbage collect once a day before bed" strategy is working out ;-). (Plus also I wonder how much of the uncollected garbage just gets paged out by the OS and never touched again.)

thom 4y ago

I like to do this to ensure GC happens occasionally, when I focus away from Emacs: (add-function :after after-focus-change-function (lambda () (unless (frame-focus-state) (garbage-collect))))

dilap 4y ago
Ah, neat idea! Thanks!