3

My system freezes for 1-2 seconds every time I need to input a password, most of the times when I start typing on the a new window or dash input and every time when I turn volume up/down through the keyboard. Probably it happens on other situations, but these are the most noticeable ones.

I am investigating it already for a long time and these are the conditions for it to happen:

  1. Ubuntu 18.04
  2. Gnome shell
  3. xorg display server
  4. Portuguese (Brazil) layout among input sources options

The problem doesn't happen if I: 1. use Ubuntu 16.04 Gnome 1. switch the interface to cinnamon or KDE on 18.04 1. switch to wayland on 18.04 1. remove Portuguese (Brazil) from input sources options

The weird thing is: if I am using English international input source it works well if and only if "Portuguese (Brazil)" is NOT among the options configured - if I add it, the problem happens even if I keep using the english input source config.

My system default language is english - maybe this is causing some kind of conflict. I don't want to use portuguese as system language because some names just get horrible (like "Área de Trabalho").

No useful info on syslog and already tried everything here: Keyboard input lag in Ubuntu 18.04 (looks like a different problem)

Do anyone have any tip that may help? I like cinnamon but not as much as gnome shell...

Thank you very much!

Luiz Fernando Schrickte
  • 113
  • My problem is very close to this one: https://askubuntu.com/questions/968788/keyboard-input-lags-on-ubuntu-17-10?rq=1 (couldn't comment there as no reputation enough).. tried the solution presented in there and didn't work here. – Luiz Fernando Schrickte May 28 '18 at 20:51
  • After every related update on ubuntu I check it again, but the problem persists. Using cinnamon for now :( – Luiz Fernando Schrickte Jul 26 '18 at 13:17

2 Answers2

4

The comment below was the solution that worked for me. I found it at https://bugs.launchpad.net/ubuntu/+source/meta-gnome3/+bug/1777708 and the author of this answer is Pedro Palhares.

After being annoyed by this bug for a long time, i started digging and found a workaround. Today i found that the bug is only present when i'm using certain keyboard layouts ("Portugues (Brasil)") and was not present when i changed the layout to EUA and language to English (need to set them both to English).

After some digging i found out the culprit is the ScrollLock key and that can be fixed by editing the layout file, which in my case is found at /usr/share/X11/xkb/symbols/br. The only modification i did was to remove or comment the line: modifier_map Mod3 { Scroll_Lock }; After that, set the language and layout back to Portugues (Brasil) and the problem was gone!

No more delays between typings. (Fedora and Ubuntu)

Gustavo Silva
  • 56
1

The input for passwords and text is now working well, without delays. Maybe some Ubuntu/gnome update (dont' know which exact update fixed it - was using cinnamon and just now tried gnome shell again).

The volume/brightness change delay is still happening, but this looks like a different problem as the screen freezes too for 1 to 2 seconds. Described the problem in a new thread: Volume and brighness adjustment OSD delay and screen freeze on Ubuntu 18.04

Luiz Fernando Schrickte
  • 113