Emacs becoming very slow


my Emacs (using Centaur Emacs since a few months) is becoming very slow after coding in Tidal for a while (~ an hour). CPU usage is increasing and it seems to take more RAM. This can get a bit hard to investigate so I just wanted to ask whether this is a somehow known problem with obvious reasons or has happened to anyone here before.

Well... learned that using the profiler in Emacs is a good thing (M x profiler-start).

I had a snippet running to always have the last output line of the *tidal* visible which involved buffer-tail. This turned out to cause heavy CPU load after a while.


since quite a while my Emacs again (or still? I don't know because this a completely new installation) will pause while editing Tidal code. Sometimes It seems to be linked to using the backspace key. I have filed an issue on the Github haskell-mode project hoping that an Emacs profiler output might track the error down for the initiated ones.

Does anyone can report the same or a similar behaviour? Any hints to how I might be able to resolve this or at least get more specific information maybe to update the mentioned issue on Github?

(I am using a Thinkpad Yoga 1. Gen, 16 MB RAM, Intel Core i7-6600U CPU @ 2.60GHz × 2 with Linux Mint 20.3 Cinnamon and Emacs 27.1.; tidal-mode is tidal-20210211.1531 and haskell-mode is haskell-mode-20210908.1543 - if that is some crucial information)


yeah, my emacs freezes when evaluating lines. in my experience the more lines i eval, the longer the freeze gets… i’ve had this problem on debian, arch, and osx.

i’m afraid i don’t have any fixes

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Yes, exactly. Furthermore my impression is: the longer I am in Tidal mode and work with it, the slower Emacs becomes... Thanks for confirming!

So, if I may ask, what editor are you using instead?

i’m still using emacs!

while the problem is annoying it doesn’t make tidal unusable until ~90 mins or so on my machine, and i don’t often have it running that long.

i don’t know much about emacs or debugging it but i might take a crack at figuring this out. ill post any findings :slight_smile:

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