Re: emacs-27 b46c75b: xref-matches-in-files: Big Tramp speed-up

[Michael Albinus <michael.albinus@gmx.de>]

Stefan Monnier <monnier@iro.umontreal.ca> writes:

> But in the current case, we just replace N calls to `file-local-name` with
> N calls to `tramp-file-local-name` and it's supposedly already much
> faster, even though `tramp-file-local-name` doesn't get to share work
> between all those calls, AFAIK.  It's *this* speed difference which I'd
> like to understand.

I said it already several times: it is tramp-file-name-handler, invoked
for every single file, which makes the major difference.

And I don't know how to change its work significantly.

>> That's why I have proposed to find a way to apply an operation to a
>> fileset instead of a single file only.
>
> Yes, the idea makes sense.  Basically add a magic-file-op
> (file-list-apply FUNCTION DIR FILES &rest ARGS) where FILES are relative
> to DIR?

Something like this, yes. However, in the case Dmitry is interested in,
FILES would be remote file names instead of relative file names. He
wanted to know the local file name part of the FILES.

I will see how it could look like. Later this week.

>         Stefan

Best regards, Michael.