Arch Linux

Potomac

Member

Registered: 2011-12-25

Posts: 528

print dialog box takes too much time to appear on Qt applications

Hello,

with cups 2.2.4 I notice that the "print dialog box" takes a long time to appear on screen on Qt applications ( the menu "file, print" in kate for example ),

it takes 5 seconds to appear on screen on Qt applications,
with an old version of cups ( 2.2.1 ) the time is much quicker : 1 second,

I don't think it's normal, maybe it's related to this bug, a patch has been released with a lot of "debug - printf" statements, which can slow the process :

https://bugs.archlinux.org/task/54695

the suspicious patch :

https://git.archlinux.org/svntogit/pack … kages/cups

I use plasma 5 with the oxygen theme, my printer is a canon LBP3000, which uses a 32 bit driver ( driver needs lib32-libcup ),
on GTK2/GTK3 applications the problem doesn't exist, the print dialog box appears quickly

Last edited by Potomac (2017-07-09 14:41:18)

Potomac

Member

Registered: 2011-12-25

Posts: 528

Re: print dialog box takes too much time to appear on Qt applications

I have found the culprit : avahi-daemon

if I disable avahi-daemon then the print dialog box appears quickly ( less than 1 second )

# systemctl stop avahi-daemon.socket
# systemctl stop avahi-daemon.service

# systemctl disable avahi-daemon.socket
# systemctl disable avahi-daemon.service

is it safe to disable avahi-daemon ?

https://wiki.archlinux.org/index.php/Avahi

Potomac

Member

Registered: 2011-12-25

Posts: 528

Re: print dialog box takes too much time to appear on Qt applications

I created a bug report :

https://github.com/apple/cups/issues/5049

because the culprit is in fact cups 2.2.4, a new feature for supporting "bonjour printers" has been added in cups 2.2.4, there is probably a bug when cups tries to call avahi-daemon

Last edited by Potomac (2017-07-09 18:51:24)