Bug#1057459: systemd: journald polluting dmesg buffer with repeated rotation messages

[Vallo Kallaste]

Package: systemd
Version: 252.17-1~deb12u1
Severity: normal
X-Debbugs-Cc: m1n...@posteo.ee

Dear Maintainer,

Removing /var/log/journal or setting Storage=volatile in
/etc/systemd/journald.conf leads to pollution of dmesg buffer with
messages like below. This was not the case in Debian 11.
I intend to log only to ephemeral /run/log/journal storage and expect
log rotations to not pollute kernel message buffer.
This is a system with 2GB of RAM and hence ~200MB tmpfs /run:

/--/
# df -h /run
Filesystem Size Used Avail Use% Mounted on
tmpfs 197M 9.4M 188M 5% /run
# free -m
total used free shared buff/cache available
Mem: 1966 315 1603 9 195 1651
Swap: 0 0 0
/--/

/--/
syslog:info : [ 1530.305989] systemd-journald[201]: Data hash table of /run/log/journal/1291a3ff2de3409fac97aa1895ef7cd4/system.journal has a fill level at 75.0 (3362 of 4480 items, 2580480 file size, 767 bytes per hash table item), suggesting rotation.
syslog:info : [ 1530.312764] systemd-journald[201]: /run/log/journal/1291a3ff2de3409fac97aa1895ef7cd4/system.journal: Journal header limits reached or header out-of-date, rotating.
syslog:info : [ 1540.509704] systemd-journald[201]: Data hash table of /run/log/journal/1291a3ff2de3409fac97aa1895ef7cd4/system.journal has a fill level at 75.0 (3361 of 4480 items, 2580480 file size, 767 bytes per hash table item), suggesting rotation.
syslog:info : [ 1540.518605] systemd-journald[201]: /run/log/journal/1291a3ff2de3409fac97aa1895ef7cd4/system.journal: Journal header limits reached or header out-of-date, rotating.
syslog:info : [ 1550.720364] systemd-journald[201]: Data hash table of /run/log/journal/1291a3ff2de3409fac97aa1895ef7cd4/system.journal has a fill level at 75.0 (3361 of 4480 items, 2580480 file size, 767 bytes per hash table item), suggesting rotation.
syslog:info : [ 1550.730576] systemd-journald[201]: /run/log/journal/1291a3ff2de3409fac97aa1895ef7cd4/system.journal: Journal header limits reached or header out-of-date, rotating.
/--/


-- Package-specific info:

-- System Information:
Debian Release: 12.2
APT prefers stable-updates
APT policy: (500, 'stable-updates'), (500, 'stable-security'), (500, 'stable')
Architecture: amd64 (x86_64)

Kernel: Linux 6.1.0-13-amd64 (SMP w/2 CPU threads; PREEMPT)
Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8), LANGUAGE not set
Shell: /bin/sh linked to /usr/bin/dash
Init: systemd (via /run/systemd/system)

Versions of packages systemd depends on:
ii libacl1 2.3.1-3
ii libaudit1 1:3.0.9-1
ii libblkid1 2.38.1-5+b1
ii libc6 2.36-9+deb12u3
ii libcap2 1:2.66-4
ii libcryptsetup12 2:2.6.1-4~deb12u1
ii libfdisk1 2.38.1-5+b1
ii libgcrypt20 1.10.1-3
ii libkmod2 30+20221128-1
ii liblz4-1 1.9.4-1
ii liblzma5 5.4.1-0.2
ii libmount1 2.38.1-5+b1
ii libp11-kit0 0.24.1-2
ii libseccomp2 2.5.4-1+b3
ii libselinux1 3.4-1+b6
ii libssl3 3.0.11-1~deb12u2
ii libsystemd-shared 252.17-1~deb12u1
ii libsystemd0 252.17-1~deb12u1
ii libzstd1 1.5.4+dfsg2-5
ii mount 2.38.1-5+b1

Versions of packages systemd recommends:
ii chrony [time-daemon] 4.3-2+deb12u1
ii dbus [default-dbus-system-bus] 1.14.10-1~deb12u1

Versions of packages systemd suggests:
ii libfido2-1 1.12.0-2+b1
pn libqrencode4 <none>
pn libtss2-esys-3.0.2-0 <none>
pn libtss2-mu0 <none>
pn libtss2-rc0 <none>
pn polkitd | policykit-1 <none>
pn systemd-boot <none>
pn systemd-container <none>
pn systemd-homed <none>
pn systemd-resolved <none>
pn systemd-userdbd <none>

Versions of packages systemd is related to:
ii dbus-user-session 1.14.10-1~deb12u1
pn dracut <none>
ii initramfs-tools 0.142
ii libnss-systemd 252.17-1~deb12u1
ii libpam-systemd 252.17-1~deb12u1
ii udev 252.17-1~deb12u1

-- no debconf information

[Luca Boccassi]

Control: tags -1 wontfix
Control: close -1

On Tue, 05 Dec 2023 11:50:13 +0000 Vallo Kallaste <m1n...@posteo.ee>
wrote:

> Package: systemd
> Version: 252.17-1~deb12u1
> Severity: normal
> X-Debbugs-Cc: m1n...@posteo.ee
>
> Dear Maintainer,
>
> Removing /var/log/journal or setting Storage=volatile in
> /etc/systemd/journald.conf leads to pollution of dmesg buffer with
> messages like below. This was not the case in Debian 11.
> I intend to log only to ephemeral /run/log/journal storage and expect
> log rotations to not pollute kernel message buffer.
> This is a system with 2GB of RAM and hence ~200MB tmpfs /run:

This is not "pollution", this is entirely expected, when there's a
rotation there's a log message. You can change the sizes so that
rotations are less frequent:

https://www.freedesktop.org/software/systemd/man/252/journald.conf.html#SystemMaxUse=

--
Kind regards,
Luca Boccassi