Re: [O] footnote fontify causing massive slowdown

[Nicolas Goaziou]

Hello,

Aaron Ecay <address@hidden> writes:

> Indeed.  However, this code was needlessly slow because it failed to
> take advantage of short-circuit evaluation.

According to the profile report, I don't understand the logic of your
patch.

>>>              - org-footnote-in-valid-context-p 4106  44%
>>>               + org-inside-LaTeX-fragment-p 2380  25%
>>>               + org-in-block-p 1563  16%
>>>               + org-in-verbatim-emphasis 159   1%

ISTM that `org-in-block-p' is marginally slower (15%) than
`org-inside-LaTeX-fragment-p' (9%).

Of course, in OP's report, `org-in-block-p' is the test returning early,
so pushing it earlier is faster since you don't call
`org-inside-LaTeX-fragment-p', but this is only a very specific
optimization made at the expense of other cases (and contradicts your
commit message). Am I missing something?

I don't understand either the benefit of adding `not' calls all over the
place. I generally use de Morgan's law the other way and save a few
primcalls.

> Do [1]-type footnotes present other performance problems today?

The main problem of plain footnotes isn't really their performance, but
false positives'. Anytime something looks like a footnote in a buffer,
you get a performance hit. This happens much more often with plain
footnotes than with other footnote types.

Moreover, false positives can introduce not-so-subtle problems during
export (see for example 2c66e40c).

Note that suggesting to not use them (the default value, actually, per
`org-footnote-auto-label') doesn't help, since false positives are the
problem, not real footnotes.

Eventually, removing them doesn't remove any feature to Org. Of course,
this is an incompatible change, and some users will need to update
documents using plain footnotes. We can provide a function for that, and
use `org-lint' to check for obsolete footnotes. The benefit is to avoid
a whole class of problems.


Regards,

-- 
Nicolas Goaziou