Re: [PATCH] Babel evaluation: location and timing information

[Max Nikulin]

On 22/09/2022 14:03, Timothy wrote:
> > On 18/09/2022 10:09, Timothy wrote:
> > > and now this might look like so:
> > > ┌────
> > > │ executing Emacs-Lisp call on line 143…
> > > │ Code block evaluation complete (took 0.2s).
> > > └────
> >
> > I do not mind to have such feature, but I am unsure concerning its price. I just
> > have tried
> >
> > (benchmark-run 1 (line-number-at-pos))
> >
> > (2.244481896 0 0.0)
> What on earth did you run that on? I ran that on the last line of the Org manual
> and here’s what I got:
>
> ┌────
> │ (0.000219268 0 0.0)
> └────

Intel(R) Core(TM) i5-4210U CPU @ 1.70GHz
It is an 8 years old laptop, minimal CPU frequency is 0.8GHz.

Org manual is ~5 times smaller than my file with notes and the former 
contains not so much not ASCII characters.

For your test I get reasonable numbers
Emacs-26 0.038 or 0.084
Emacs-27 0.0066 or 0.0092

I am comfortable with performance. It seems, some optimization has been 
done in Emacs since 26 release. I do not see dependence on Org version.

While I work with my notes file, performance degrades after some 
operations. E.g. searches become significantly slower after caching 
refile targets. Previous discussion of the issue:
Ihor Radchenko. Re: profiling latency in large org-mode buffers (under 
both main & org-fold feature) Sun, 27 Feb 2022 14:43:29 +0800. 
https://list.orgmode.org/87y21wkdwu.fsf@localhost

My experience is that e.g. emacsclient with particular line causes 
several seconds hang.

Despite improvements since Emacs-26 in line counting, still I believe 
that the `line-number-at-pos' function may still be excessively 
expensive in real live when unconditionally used just for a bit nicer 
logging.