Your message dated Sat, 29 Aug 2026 16:18:10 +0200
with message-id <[email protected]>
and subject line Re: Bug#1125313: libc6: Performance regression in KDE/Qt apps
after update to 2.41-12+deb13u1
has caused the Debian Bug report #1125313,
regarding libc6: Performance regression in KDE/Qt apps after update to
2.41-12+deb13u1
to be marked as done.
This means that you claim that the problem has been dealt with.
If this is not the case it is now your responsibility to reopen the
Bug report if necessary, and/or fix the problem forthwith.
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--
1125313: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1125313
Debian Bug Tracking System
Contact [email protected] with problems
--- Begin Message ---
Package: libc6
Version: 2.41-12+deb13u1
Severity: important
X-Debbugs-Cc: [email protected]
Dear Maintainer,
After upgrading to glibc 2.41-12+deb13u1 (Debian 13.3 point release on
January 10, 2026), all KDE/Qt applications experience severe startup
delays of 1-3 seconds. Previously these applications started instantly.
What led up to the situation:
System was updated with 'apt upgrade' which included the glibc update
from the 13.3 point release.
What exactly did you do:
Tested multiple terminals and applications:
- Konsole: 2-3 second startup delay
- Alacritty: 1-2 second startup delay
- Other Qt/KDE applications show similar slowdown
- Non-Qt applications (xterm) start instantly
What was the outcome:
All Qt/KDE applications now have significant startup delays making the
system feel sluggish and unresponsive.
What outcome did you expect:
Applications should start instantly as they did before the update.
Additional information:
- Tested on both kernel 6.12.57 and 6.12.63 - issue persists on both
- GLIBC_TUNABLES=glibc.rtld.execstack=1 workaround does NOT resolve the issue
- Intel Iris Xe Graphics (amd64), KDE Plasma on Wayland
- This represents a significant usability regression for a stable release
-- System Information:
Debian Release: 13.3
APT prefers stable-updates
APT policy: (500, 'stable-updates'), (500, 'stable-security'), (500, 'stable')
Architecture: amd64 (x86_64)
Kernel: Linux 6.12.63+deb13-amd64 (SMP w/8 CPU threads; PREEMPT)
Kernel taint flags: TAINT_PROPRIETARY_MODULE, TAINT_OOT_MODULE,
TAINT_UNSIGNED_MODULE
Locale: LANG=en_GB.UTF-8, LC_CTYPE=en_GB.UTF-8 (charmap=UTF-8),
LANGUAGE=en_GB:en
Shell: /bin/sh linked to /usr/bin/dash
Init: systemd (via /run/systemd/system)
LSM: AppArmor: enabled
Versions of packages libc6 depends on:
ii libgcc-s1 14.2.0-19
Versions of packages libc6 recommends:
ii libidn2-0 2.3.8-2
Versions of packages libc6 suggests:
ii debconf [debconf-2.0] 1.5.91
pn glibc-doc <none>
ii libc-l10n 2.41-12+deb13u1
pn libnss-nis <none>
pn libnss-nisplus <none>
ii locales 2.41-12+deb13u1
-- debconf information excluded
--- End Message ---
--- Begin Message ---
On 2026-03-28 14:12, Aurelien Jarno wrote:
> Hi,
>
> On 2026-01-13 20:03, Aurelien Jarno wrote:
> > Hi,
> >
> > On 2026-01-12 12:15, chris wrote:
> > > Package: libc6
> > > Version: 2.41-12+deb13u1
> > > Severity: important
> > > X-Debbugs-Cc: [email protected]
> > >
> > > Dear Maintainer,
> > >
> > > After upgrading to glibc 2.41-12+deb13u1 (Debian 13.3 point release on
> > > January 10, 2026), all KDE/Qt applications experience severe startup
> > > delays of 1-3 seconds. Previously these applications started instantly.
> > >
> > > What led up to the situation:
> > > System was updated with 'apt upgrade' which included the glibc update
> > > from the 13.3 point release.
> >
> > Have you been able to confirm the issue actually comes from this new
> > glibc version? For instance you can try downgrading it to version
> > 2.41-12 and check it solves the issue.
> >
> > > What exactly did you do:
> > > Tested multiple terminals and applications:
> > > - Konsole: 2-3 second startup delay
> > > - Alacritty: 1-2 second startup delay
> > > - Other Qt/KDE applications show similar slowdown
> > > - Non-Qt applications (xterm) start instantly
> >
> > I have tried to reproduce the issue, but I haven't been able to so far.
> > Also looking at the change introduced in this new version, I haven't
> > been able to find an obvious culprit in the commit backported in this
> > version.
> >
> > Could you please try to run any of the software having an issue under
> > strace and share the output? That could give a hint at what is wrong.
> > You might want to use the -tt option to get timestamp and the -o option
> > to save the log.
>
> Any news on that?
No answer from the submitted, and nobody else reported the issue.
Closing.
Regards
Aurelien
--
Aurelien Jarno GPG: 4096R/1DDD8C9B
[email protected] http://aurel32.net
--- End Message ---
