Hi,
On 12/7/21 1:34 PM, Benjamin Brunner wrote:
>>>> Please correct me if I am wrong, I see the difference of the KillMode is,
>>>> -- KillMode=mixed stops the processes more gentally, it kill the main
>>>> process with SIGTERM and the remaining processes with SIGKILL.
>>>> -- KillMode=control-group kills all in-cgroup processes with SIGKILL,
>>>> which I feel a bit cruel for the main process.
I think there's a miss-understanding here.
Regardless of whether "mixed" or "control-group" mode (or any other mode
actually) is used, the process used to kill processes part of a service is
always the same, only the list of the killed processes differs.
The process is as follow:
1. send the signal specified by KillSignal= to the list of processes (if
any), TERM is the default
2. wait until either the target of process(es) exit or a timeout expires
3. if the timeout expires send the signal specified by FinalKillSignal=,
KILL is the default
For "control-group", all remaining processes will receive the SIGTERM signal (by
default) and if there are still processes after a period f time, they will get
the SIGKILL signal.
For "mixed", only the main process will receive the SIGTERM signal, and if there
are still processes after a period of time, all remaining processes (including
the main one) will receive the SIGKILL signal.
>>> There is no point sending SIGTERM to a process which doesn't respond to
>>> it. mdmon is the only mdadm service which handles SIGTERM. So it might
>>> make sense to uise KillMode=mixed for that.
>>> For anything else, SIGKILL via KillMode=control-group is perfectly
>>> acceptable.
I don't know enough mdadm to suggest a mode but maybe the clarification above
will help you figuring this out.
That said it sounds a bit strange that some processes don't respond to SIGTERM.
Is that done because some services need to run lately during the shutdown process ?
Thanks.
