Bug#1096033: libgtk-4-1: first startup of programs depending on libgtk-4-1 4.17.4+ds-4 very slow, often lagging minutes

[msp]

Package: libgtk-4-1
Version: 4.17.4+ds-4
Severity: important
X-Debbugs-Cc: gamma4258 at mailbox.org

When libgtk-4-1:amd64 is installed in version 4.17.4+ds-4, starting any
programs depending on this package takes unusually long (up to minutes),
sometimes causing the program to be unusable.

This is not a CPU load issue (as verified using top).
It is also independent of any gnome user settings, as it happens with a
freshly added user, and also using e.g. icewm.
I downgraded adwaita-icon-theme:amd64 from 48-beta-3 to 47.0-2 to
check if the issue is related to #1095301, but this did not help either.

The issue might however be related to gir1.2-gtk-4.0:amd64, which gets
installed with libgtk-4-1.

To track down the issue I tried starting various programs with strace.

'strace gnome-control-center' hangs at

eventfd2(0, EFD_CLOEXEC|EFD_NONBLOCK)   = 12
futex(0x55b3f83b5648, FUTEX_WAKE_PRIVATE, 1) = 1
ppoll([{fd=12, events=POLLIN}], 1, {tv_sec=24, tv_nsec=999978000}, NULL, 8


'strace audacity' hangs at

eventfd2(0, EFD_CLOEXEC|EFD_NONBLOCK)   = 10
write(9, "\1\0\0\0\0\0\0\0", 8)         = 8
futex(0x561cff6605b0, FUTEX_WAKE_PRIVATE, 1) = 1
ppoll([{fd=10, events=POLLIN}], 1, {tv_sec=24, tv_nsec=999982000}, NULL, 8


'strace libreoffice', hangs twice during startup, each time at this line:

...
recvmsg(3, {msg_namelen=0}, 0)          = -1 EAGAIN (Resource temporarily
unavailable)
recvmsg(3, {msg_namelen=0}, 0)          = -1 EAGAIN (Resource temporarily
unavailable)
read(4,

Deinstalling libreoffice-gtk3 resolves the issue, which helped me
track down the issue to being related to gtk, i.e. either libgtk-4-1 or
gir1.2-gtk-4.0.

I hope this helps,
tha     nks!



-- System Information:
Debian Release: trixie/sid
  APT prefers testing
  APT policy: (500, 'testing'), (50, 'unstable'), (1, 'experimental')
Architecture: amd64 (x86_64)
Foreign Architectures: i386

Kernel: Linux 6.12.13-amd64 (SMP w/8 CPU threads; PREEMPT)
Kernel taint flags: TAINT_OOT_MODULE, TAINT_UNSIGNED_MODULE
Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8), LANGUAGE=en_US:en
Shell: /bin/sh linked to /usr/bin/dash
Init: systemd (via /run/systemd/system)
LSM: AppArmor: enabled

Versions of packages libgtk-4-1 depends on:
ii  adwaita-icon-theme            47.0-2
ii  hicolor-icon-theme            0.18-2
ii  libc6                         2.40-6
ii  libcairo-gobject2             1.18.2-2
ii  libcairo-script-interpreter2  1.18.2-2
ii  libcairo2                     1.18.2-2
ii  libcloudproviders0            0.3.6-1+b1
ii  libcolord2                    1.4.7-1+b2
ii  libcups2t64                   2.4.10-2+b1
ii  libepoxy0                     1.5.10-2
ii  libfontconfig1                2.15.0-2
ii  libfribidi0                   1.0.16-1
ii  libgdk-pixbuf-2.0-0           2.42.12+dfsg-2
ii  libgles2                      1.7.0-1+b2
ii  libglib2.0-0t64               2.83.3-2
ii  libgraphene-1.0-0             1.10.8-5
ii  libgtk-4-common               4.17.4+ds-4
ii  libharfbuzz-subset0           10.2.0-1
ii  libharfbuzz0b                 10.2.0-1
ii  libjpeg62-turbo               1:2.1.5-3+b1
ii  libpango-1.0-0                1.56.1-1
ii  libpangocairo-1.0-0           1.56.1-1
ii  libpangoft2-1.0-0             1.56.1-1
ii  libpng16-16t64                1.6.46-4
ii  libtiff6                      4.5.1+git230720-5
ii  libvulkan1                    1.4.304.0-1
ii  libwayland-client0            1.23.1-1
ii  libwayland-egl1               1.23.1-1
ii  libx11-6                      2:1.8.10-2
ii  libxcursor1                   1:1.2.3-1
ii  libxdamage1                   1:1.1.6-1+b2
ii  libxext6                      2:1.3.4-1+b3
ii  libxfixes3                    1:6.0.0-2+b4
ii  libxi6                        2:1.8.2-1
ii  libxinerama1                  2:1.1.4-3+b3
ii  libxkbcommon0                 1.7.0-2
ii  libxrandr2                    2:1.5.4-1+b3
ii  shared-mime-info              2.4-5+b2

Versions of packages libgtk-4-1 recommends:
ii  iso-codes                 4.17.0-1
pn  libgtk-4-bin              <none>
pn  libgtk-4-media-gstreamer  <none>
ii  librsvg2-common           2.59.90+dfsg-2

Versions of packages libgtk-4-1 suggests:
ii  gvfs  1.57.1-1

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