Worked on back in 2024 for the Linux kernel was [1]a built-in counter to keep track of the number of hung tasks since boot . That feature for keeping track of the number of hung tasks since boot was [2]merged in Linux 6.13 and exposed via /proc/sys/kernel/hung_task_detect_count . For helping ease use around it, new code working its way to the kernel will allow resetting that "hung_task_detect_count" counter.

From Linux 6.13 to now the /proc/sys/kernel/hung_task_detect_count has just provided a numeric indicator for the number of hung tasks since boot time. But for helping ease monitoring of such Linux servers/systems, patches working their way via the MM tree will allow resetting that counter. Simply writing 0 to the /proc/sys/kernel/hung_task_detect_count will allow resetting that counter. Such as if applying live kernel updates or other system changes in an effort to address prior hangs without a reboot, now you will be able to easily reset that counter rather than having to remember its former value for comparison.

Pretty straight forward and a bit surprising that functionality wasn't in place from the start. In any event those curious about this pending support for being able to zero out the hung task detector at run-time can see [3]this patch for all the details. A small but useful addition.



[1] https://www.phoronix.com/news/Linux-hung_task_detect_count

[2] https://www.phoronix.com/news/Linux-6.13-Non-MM

[3] https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git/commit/?h=mm-everything&id=060aa092dc03e61ffbf74de8c32c55b8f6a75e44