On Tue 10-04-18 16:04:40, Zhaoyang Huang wrote: > On Tue, Apr 10, 2018 at 3:49 PM, Michal Hocko <mho...@kernel.org> wrote: > > On Tue 10-04-18 14:39:35, Zhaoyang Huang wrote: > >> On Tue, Apr 10, 2018 at 2:14 PM, Michal Hocko <mho...@kernel.org> wrote: [...] > >> > OOM_SCORE_ADJ_MIN means "hide the process from the OOM killer > >> > completely". > >> > So what exactly do you want to achieve here? Because from the above it > >> > sounds like opposite things. /me confused... > >> > > >> Steve's patch intend to have the process be OOM's victim when it > >> over-allocating pages for ring buffer. I amend a patch over to protect > >> process with OOM_SCORE_ADJ_MIN from doing so. Because it will make > >> such process to be selected by current OOM's way of > >> selecting.(consider OOM_FLAG_ORIGIN first before the adj) > > > > I just wouldn't really care unless there is an existing and reasonable > > usecase for an application which updates the ring buffer size _and_ it > > is OOM disabled at the same time. > There is indeed such kind of test case on my android system, which is > known as CTS and Monkey etc.
Does the test simulate a real workload? I mean we have two things here oom disabled task and an updater of the ftrace ring buffer to a potentially large size. The second can be completely isolated to a different context, no? So why do they run in the single user process context? > Furthermore, I think we should make the > patch to be as safest as possible. Why do we leave a potential risk > here? There is no side effect for my patch. I do not have the full context. Could you point me to your patch? -- Michal Hocko SUSE Labs