Console 작업 중에, 쏟아지는 이벤트(e.g. ACPI alert )등으로 작업에 어려움이 있을때, console log level(nlevel)을 임시로 조정하여 화면에 출력되는 정보를 관리할 수 있음.
dmesg
Supported log levels (priorities):
#define KERN_EMERG "<0>" /* system is unusable */
#define KERN_ALERT "<1>" /* action must be taken immediately */
#define KERN_CRIT "<2>" /* critical conditions */
#define KERN_ERR "<3>" /* error conditions */
#define KERN_WARNING "<4>" /* warning conditions */
#define KERN_NOTICE "<5>" /* normal but significant condition */
#define KERN_INFO "<6>" /* informational */
#define KERN_DEBUG "<7>" /* debug-level messages */
-n, --console-level level
Set the level at which printing of messages is done to the console. The level is a level number or abbreviation of the level name. For all supported levels see the --help output.
For example, -n 1 or -n emerg prevents all messages, except emergency (panic) messages, from appearing on the console.
All levels of messages are still written to /proc/kmsg, so syslogd(8) can still be used to control exactly where kernel messages appear. When the -n option is used, dmesg will not print or clear the kernel ring buffer.
정보출처:
지인(박ㅇㅇ님)의 가르침+
https://www.kernel.org/doc/html/latest/core-api/printk-basics.html
https://man7.org/linux/man-pages/man1/dmesg.1.html
https://jybaek.tistory.com/130