bug#54025: 27.2; dired-do-find-regexp skips occurences

[Dmitry Gutov]

Hi Michael,

On 25.02.2022 17:05, Michael Albinus wrote:

> > On 25.02.2022 10:13, Michael Albinus wrote:
> > > Tramp does not use caches when computing
> > > verify-visited-file-modtime. Let's see how it goes.
> >
> > I certainly hope that it doesn't invoke a remote call every time this
> > function is called (when called locally, it hits the disk).
>
> verify-visited-file-modtime needs to read the file-attributes. That's
> the idea of this function.

IIUC Tramp caches some information about files, and flushes those cashes 
after "destructive" operations. "Last modification time" could reside in 
such a cache.

> Yes, every time it is called, it goes remote.

Thanks for the confirmation. I guess we need to predicate that check on 
the file being local, because the worst-case performance in our scenario 
(remote system with high rtt) could be very bad.

We might even drop if later if some hdd users see a slowdown in common 
scenarios. It's a secondary check, after all.

Commit 018eeb655a.