Package: munin-plugins-c Version: 0.0.11-1 Severity: normal Dear Maintainer,
the open_files plugin seems not to be able to cope with very large values for max files. On two of my machines it returns 0 as warning and critical thresholds for the number of open files. I believe this is because it does not handle the value for max files correctly. Actual output: root@nephthys:~# munin-run open_files used.value 11008 max.value -1 root@nephthys:~# munin-run open_files config graph_title File table usage graph_args --base 1000 -l 0 graph_vlabel number of open files graph_category system graph_info This graph monitors the Linux open files table. used.label open files used.info The number of currently open files. max.label max open files max.info The maximum supported number of open files. Tune by modifying /proc/sys/fs/file-nr. used.warning 0 used.critical 0 Because the current value for open files used.value is larger than the threshold of used.critical 0, munin alerts this. As the config output suggests, I looked at the kernel configuration: root@nephthys:~# cat /proc/sys/fs/file-nr 11136 0 18446744073709551615 The value for max_files is the largest unsigned 64bit integer and would be -1 if incorrectly interpreted as signed. As the standard perl equivalent for open_files calculates the warning and critical values from the max value, I assume this step fails. Expected output: The output would be fine if it were the same as the perl plugin's: root@nephthys:~# munin-run open_files used.value 11424 max.value 18446744073709551615 root@nephthys:~# munin-run open_files config graph_title File table usage graph_args --base 1000 -l 0 graph_vlabel number of open files graph_category system graph_info This graph monitors the Linux open files table. used.label open files used.info The number of currently open files. used.warning 16971004547812788224 used.critical 18077809192235360256 max.label max open files max.info The maximum supported number of open files. Tune by modifying /proc/sys/fs/file-max. An alternative would be to simply not output warning and critical levels when the max value is so huge. Kind regards Marc -- System Information: Debian Release: buster/sid APT prefers testing APT policy: (745, 'testing'), (500, 'stable'), (400, 'unstable'), (300, 'experimental') Architecture: amd64 (x86_64) Foreign Architectures: i386 Kernel: Linux 4.19.0-2-amd64 (SMP w/4 CPU cores) Kernel taint flags: TAINT_OOT_MODULE, TAINT_UNSIGNED_MODULE Locale: LANG=C.UTF-8, LC_CTYPE=en_GB.UTF-8 (charmap=UTF-8), LANGUAGE=C.UTF-8 (charmap=UTF-8) Shell: /bin/sh linked to /bin/dash Init: systemd (via /run/systemd/system) LSM: AppArmor: enabled Versions of packages munin-plugins-c depends on: ii libc6 2.28-7 munin-plugins-c recommends no packages. munin-plugins-c suggests no packages. -- no debconf information
