Subject: Re: bug#57207: 29.0.50; Fontification is slow after e7b5912b23 (Improvements to long lines handling)

From: Ihor Radchenko <[email-masked]>
Date: Mon, 15 Aug 2022 19:39:35 +0800

Gregory Heytings <[email-masked]> writes:

>> Do you have any idea what could be going wrong or how to debug things 
>> further?
>>
>
> Can you (a) provide a MRE so that we could track down what's going on 
> and/or (b) try to set long-line-threshold to a larger value (20000, 50000, 
> 100000) and see when the performance degradation disappears?

(a) It is hard. The problem appears when using a combination of a 20Mb
Org file and WIP Org mode branch.

(b) Setting long-line-threshold to nil makes the slowdown disappear.
Increasing long-line-threshold to 100000 made Emacs hang. I had to kill
it using kill -9.

-- 
Ihor Radchenko,
Org mode contributor,
Learn more about Org mode at https://orgmode.org/.
Support Org development at https://liberapay.com/org-mode,
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