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

From: Петров Андрей <[email-masked]>
Date: Sat, 26 Feb 2022 14:54:39 +0000

Michael, Dmitry,

- I think it is not the best idea to search in files and directories
  visited through tramp (does internal grep call have an optimized
  version for that?).

- I believe what saving buffers before operation involves more traffic
  then checking for modification time.

- Also if I remember correctly I saw some inflating transcoding while
  copying files into local machine using tramp (that's why I prefer
  using tar/ssh/untar or scp over dired tools for copying files
  between machines) - aggressive traffic optimization is not always
  used.

- When I trying to type something in buffer visiting modified from
  outside file I am prompted to confirm my intention (really edit the
  buffer?) - if I'm not wrong, it should involve some network
  activity.

So does the time modification checking give so much overhead? I found
the synchronizing of search results in xref buffers with buffer
contents (when you passes through an xref) very comfortable. It might
be more confusing when user clicks to xref and jumps into non-matching
text area.

Best regards,
Andrey Petrov.

________________________________________
От: Michael Albinus <[email-masked]>
Отправлено: 26 февраля 2022 г. 16:56:51
Кому: Dmitry Gutov
Копия: [email-masked]; Петров Андрей
Тема: Re: bug#54025: 27.2; dired-do-find-regexp skips occurences

Dmitry Gutov <[email-masked]> writes:

> Hi Michael,

Hi Dmitry,

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

In general, this is correct. But verify-visited-file-modtime is
different. Its task is to check, whether the buffer's known file
modification time is still valid; it could have changed on disk due to
external changes or so. That's why it cannot use the Tramp cache.

Best regards, Michael.