2012/4/18 Frederic Weisbecker <fweisbec@xxxxxxxxx>: > On Tue, Apr 17, 2012 at 08:17:53AM -0700, Tejun Heo wrote: >> Hello, Frederic. >> >> On Thu, Apr 12, 2012 at 06:59:27PM +0200, Frederic Weisbecker wrote: >> > I want: >> > >> > a) to prevent the forkbomb from going far enough to DDOS the machine >> > b) to be able to kill that forkbomb once detected, in one go without race >> > against concurrent forks. >> > >> > I think a) can work just fine with kernel stack limiting. I also need >> > to be notified about the fact we reached the limit. And b) should >> > be feasible with the help of the cgroup freezer. >> >> kmem allocation fail after reaching the limit which in turn should >> fail task creation. Isn't that the same effect as the task_counter as >> implemented? > > That's it. > >> >> > > Is there anything for which you need to know exactly the number of >> > > processes? >> > >> > No that's really about prevent/kill forkbomb as far as I'm concerned. >> >> Hmm... so, accounting overhead aside, if the only purpose is >> preventing the whole machine being brought down by a fork bomb, kmem >> limiting is enough, right? > > I think so yeah. But this needs to be a well defined kind of kmem I think. Relying on kernel memory alone is too general to just protect against forkbombs. Kernel stack, OTOH, should be a good criteria. But now I'm worrying, do you think this kmem.kernel_stack limitation is going to be useful for other kind of usecase? _______________________________________________ Containers mailing list Containers@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linuxfoundation.org/mailman/listinfo/containers
