Bug#1119299: cupsd has around 0.5-1% permanent CPU usage
Package: cups
Version: 2.4.14-1
Severity: normal
Dear Maintainer,
since the most recent update, I regularly see cups show up in htop when I sort
processes by CPU usage: around half the time, when the system is idle, I see
cups among the top 5 processes by CPU consumption. This is on a full GNOME
desktop system, with multiple chat applications, browsers, and IDEs all running
at the same time -- and yet cupsd manages to show up among those other,
typically much more resource-demanding processes. This is while cups should be
entirely idle, no local printer is even connected, and the two configured
network printers are not reachable either. There are no jobs in any queue.
I restarted cupsd to see if this persists, and it did: after around 4 minutes,
cups accumulated around 2s of CPU usage. That's not much, of course, but cups
does stand out in the process list sorted by total CPU time since it is
constantly moving upwards even though it shouldn't be doing anything.
I did not see this before a recent big 'apt upgrade'.
I could imagine that this is caused by some other application constantly trying
to talk to cups for no good reason, but I am not sure how I would go about
tracing that to its origin, so I am reporting the bug where I see the symptoms.
Kind regards,
Ralf
-- System Information:
Debian Release: forky/sid
APT prefers testing-debug
APT policy: (500, 'testing-debug'), (500, 'testing')
Architecture: amd64 (x86_64)
Foreign Architectures: i386
Kernel: Linux 6.16.12+deb14+1-amd64 (SMP w/20 CPU threads; PREEMPT)
Kernel taint flags: TAINT_CPU_OUT_OF_SPEC
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 cups depends on:
ii cups-client 2.4.14-1
ii cups-common 2.4.14-1
ii cups-core-drivers 2.4.14-1
ii cups-daemon 2.4.14-1
ii cups-filters 1.28.17-6
ii cups-ppdc 2.4.14-1
ii cups-server-common 2.4.14-1
ii debconf [debconf-2.0] 1.5.91
ii ghostscript 10.05.1~dfsg-3
ii libavahi-client3 0.8-17
ii libavahi-common3 0.8-17
ii libc6 2.41-12
ii libcups2t64 2.4.14-1
ii libgcc-s1 15.2.0-4
ii libstdc++6 15.2.0-4
ii libusb-1.0-0 2:1.0.29-2
ii poppler-utils 25.03.0-11.1
ii procps 2:4.0.4-9
Versions of packages cups recommends:
ii avahi-daemon 0.8-17
ii colord 1.4.8-1
Versions of packages cups suggests:
pn cups-bsd <none>
pn cups-pdf <none>
pn foomatic-db-compressed-ppds | foomatic-db <none>
ii smbclient 2:4.23.2+dfsg-1
ii udev 258.1-1
-- debconf information:
cupsys/backend: lpd, socket, usb, snmp, dnssd
cupsys/raw-print: true
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