On Mon, 07.11.11 11:09, Williams, Dan J (dan.j.williams@xxxxxxxxx) wrote: > >> What exactly is "kill_all_processes()"? is it SIGTERM or SIGKILL or both > >> with a gap or ??? > > > > SIGTERM followed by SIGKILL after 5s if the programs do not react to > > that in time. But note that this logic only applies to processes which > > for some reason managed to escape systemd's usual cgroup-based killing > > logic. Normal services are hence already killed at that time, and only > > processes which moved themselves out of any cgroup or for which the > > service files disabled killing might survive to this point. > > So I think mdmon should always try to escape itself from cgroup based > killing. It follows the lifespan of the array, and if the array is > not stopped by the cgroup exit (or the array lifespan is not > controlled in a service file), then mdmon must keep running. Well, I think when it gets killed by the cgroup-based killer then it should try to tear down its MD device. In the mdmon service file use SendSIGKILL=no to disable sending of SIGKILL after the initial SIGTERM. With KillSignal= you chan choose the signal you first want to be killed with, if you don't want it to be SIGTERM. With KillMode= you can choose whether only the main process of the service, all processes of the service, or no processes of the service shall be killed. With TimeoutSec= you can set the timeout between the SIGTERM and the SIGKILL. See systemd.service(5) for more information. > > You have relatively flexible control of the first step in this code. The > > second step is then the hammer that tries to fix up what this step > > didn't accomplish. My suggestion to check argv[0][0] was to avoid the > > hammer. > > I notice that if the rootfs is on a dm or md device systemd/shutdown > will always fall through to ultimate_send_signal() which will not > discriminate against processes flagged with '@'. Since we aren't > stopping the root md device I wonder if ultimate_send_signal() should > also ignore flagged processes, or whether the failure to stop the root > device is to be expected and let shutdown skip ultimate_send_signal() > if the only remaining work is shutting down the rootfs-blockdev. I'm > leaning towards the latter. The idea was to skip processes flgged with '@' in both the ultimate_send_signal() and send_signal() calls. Lennart -- Lennart Poettering - Red Hat, Inc. -- To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
