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

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

[Mikhail Pomaznoy]

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''

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X11 XDBE XIM XPM GTK3 ZLIB

Important settings:
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Major mode: Text

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Load-path shadows:
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bug#57279: Tramp slows down some edits of a remove file

[Michael Albinus]

Mikhail Pomaznoy <mikpom@mikpom.ru> writes:

> Greetings!

Hi Mikhail,

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

I suspect it is locking of the file. Other candidates for this behavior
could be auto-save or backup.

Locking of remote files can be suppressed by setting
remote-file-name-inhibit-locks to a non-nil value. See also the
discussion in the Tramp manual,
(info "(tramp) Auto-save File Lock and Backup")

> Kind regards,
>
> -Mikhail

Best regards, Michael.

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

[Mikhail Pomaznoy]

[-- Attachment #1: Type: text/plain, Size: 882 bytes --]

Setting |remote-file-name-inhibit-locks |to t works like a charm. 
Obviously non-bug.

Thanks,
Mikhail

On 8/19/22 14:14, Michael Albinus wrote:
> Mikhail Pomaznoy<mikpom@mikpom.ru>  writes:
>
>> Greetings!
> Hi Mikhail,
>
>> 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.
>>
>> Any help is appreciated and I am willing to help debug and investigate
>> if needed.
> I suspect it is locking of the file. Other candidates for this behavior
> could be auto-save or backup.
>
> Locking of remote files can be suppressed by setting
> remote-file-name-inhibit-locks to a non-nil value. See also the
> discussion in the Tramp manual,
> (info "(tramp) Auto-save File Lock and Backup")
>
>> Kind regards,
>>
>> -Mikhail
> Best regards, Michael.

[-- Attachment #2: Type: text/html, Size: 1902 bytes --]

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

[Michael Albinus]

Mikhail Pomaznoy <mikpom@mikpom.ru> writes:

Hi Mikhail,

> Setting remote-file-name-inhibit-locks to t works like a charm.
> Obviously non-bug.

Thanks for the feedback, I'm closing this bug. I've added also the
recipe to the Tramp manual.

> Thanks,
> Mikhail

Best regards, Michael.