bug#57279: Tramp slows down some edits of a remove file

[Mikhail Pomaznoy <mikpom@mikpom.ru>]

Greetings!

I am using Emacs+Tramp on a regular day basis and experiencing some 
performance issues.

When I make the first edit (insert any char or even hit backspace) on a 
remote file I just opened it lags. Any edit after that seems to be fine. 
Any edit after another save is slow again.

This does get worse on slow connections but this lag is quite disturbing 
even on fasty connections.

To give an idea I've recorded a screencast 
https://www.mikpom.ru/owncloud/index.php/s/PQMtZuoffSr8tP8

Any help is appreciated and I am willing to help debug and investigate 
if needed.

Kind regards,

-Mikhail


In GNU Emacs 28.1 (build 1, x86_64-pc-linux-gnu, GTK+ Version 3.24.33, 
cairo version 1.17.6)
  of 2022-04-28 built on frederik
Windowing system distributor 'The X.Org Foundation', version 11.0.12101004
System Description: Arch Linux

Configured using:
  'configure --with-x-toolkit=gtk3 --with-native-compilation
  --sysconfdir=/etc --prefix=/usr --libexecdir=/usr/lib
  --localstatedir=/var --with-cairo --with-harfbuzz --with-libsystemd
  --with-modules 'CFLAGS=-march=x86-64 -mtune=generic -O2 -pipe -fno-plt
  -fexceptions -Wp,-D_FORTIFY_SOURCE=2 -Wformat -Werror=format-security
  -fstack-clash-protection -fcf-protection -g
  -ffile-prefix-map=/build/emacs/src=/usr/src/debug -flto=auto'
  'LDFLAGS=-Wl,-O1,--sort-common,--as-needed,-z,relro,-z,now -flto=auto''

Configured features:
ACL CAIRO DBUS FREETYPE GIF GLIB GMP GNUTLS GPM GSETTINGS HARFBUZZ JPEG
JSON LCMS2 LIBOTF LIBSYSTEMD LIBXML2 M17N_FLT MODULES NATIVE_COMP NOTIFY
INOTIFY PDUMPER PNG RSVG SECCOMP SOUND THREADS TIFF TOOLKIT_SCROLL_BARS
X11 XDBE XIM XPM GTK3 ZLIB

Important settings:
   value of $LANG: en_US.UTF-8
   locale-coding-system: utf-8-unix

Major mode: Text

Minor modes in effect:
   text-scale-mode: t
   shell-dirtrack-mode: t
   tooltip-mode: t
   global-eldoc-mode: t
   show-paren-mode: t
   electric-indent-mode: t
   mouse-wheel-mode: t
   tool-bar-mode: t
   menu-bar-mode: t
   file-name-shadow-mode: t
   global-font-lock-mode: t
   font-lock-mode: t
   blink-cursor-mode: t
   auto-composition-mode: t
   auto-encryption-mode: t
   auto-compression-mode: t
   line-number-mode: t
   indent-tabs-mode: t
   transient-mark-mode: t

Load-path shadows:
None found.

Features:
(shadow sort mail-extr emacsbug message rmc puny dired dired-loaddefs
rfc822 mml mml-sec epa derived epg rfc6068 epg-config gnus-util rmail
rmail-loaddefs mm-decode mm-bodies mm-encode mail-parse rfc2231
mailabbrev gmm-utils mailheader sendmail rfc2047 rfc2045 ietf-drums
mm-util mail-prsvr mail-utils mule-util face-remap eieio-opt speedbar
ezimage dframe find-func shortdoc text-property-search cl-extra cl-print
autorevert filenotify thingatpt help-fns radix-tree help-mode
tramp-sshfs tramp-smb tramp-rclone tramp-fuse tramp-crypt tramp-cmds
url-tramp tramp-gvfs zeroconf url-util url-parse url-vars dbus xml
tramp-adb apropos cus-edit pp cus-start cus-load wid-edit vc-hg vc-git
diff-mode easy-mmode vc-bzr vc-dispatcher tramp-cache tramp-sh tramp
tramp-loaddefs trampver tramp-integration files-x tramp-compat shell
pcomplete comint ansi-color ring parse-time iso8601 time-date ls-lisp
format-spec auth-source cl-seq eieio eieio-core cl-macs eieio-loaddefs
password-cache json subr-x map seq byte-opt gv bytecomp byte-compile
cconv misearch multi-isearch cl-loaddefs cl-lib iso-transl tooltip eldoc
paren electric uniquify ediff-hook vc-hooks lisp-float-type elisp-mode
mwheel term/x-win x-win term/common-win x-dnd tool-bar dnd fontset image
regexp-opt fringe tabulated-list replace newcomment text-mode lisp-mode
prog-mode register page tab-bar menu-bar rfn-eshadow isearch easymenu
timer select scroll-bar mouse jit-lock font-lock syntax font-core
term/tty-colors frame minibuffer cl-generic cham georgian utf-8-lang
misc-lang vietnamese tibetan thai tai-viet lao korean japanese eucjp-ms
cp51932 hebrew greek romanian slovak czech european ethiopic indian
cyrillic chinese composite emoji-zwj charscript charprop case-table
epa-hook jka-cmpr-hook help simple abbrev obarray cl-preloaded nadvice
button loaddefs faces cus-face macroexp files window text-properties
overlay sha1 md5 base64 format env code-pages mule custom widget
hashtable-print-readable backquote threads dbusbind inotify lcms2
dynamic-setting system-font-setting font-render-setting cairo
move-toolbar gtk x-toolkit x multi-tty make-network-process
native-compile emacs)

Memory information:
((conses 16 190118 17434)
  (symbols 48 12206 0)
  (strings 32 43138 2401)
  (string-bytes 1 1388283)
  (vectors 16 27883)
  (vector-slots 8 498096 18941)
  (floats 8 102 174)
  (intervals 56 2739 428)
  (buffers 992 24))