On Tue, Mar 12, 2019 at 10:45 AM Sultan Alsawaf <sultan@xxxxxxxxxxxxxxx> wrote: > > On Tue, Mar 12, 2019 at 10:17:43AM -0700, Tim Murray wrote: > > Knowing whether a SIGKILL'd process has finished reclaiming is as far > > as I know not possible without something like procfds. That's where > > the 100ms timeout in lmkd comes in. lowmemorykiller and lmkd both > > attempt to wait up to 100ms for reclaim to finish by checking for the > > continued existence of the thread that received the SIGKILL, but this > > really means that they wait up to 100ms for the _thread_ to finish, > > which doesn't tell you anything about the memory used by that process. > > If those threads terminate early and lowmemorykiller/lmkd get a signal > > to kill again, then there may be two processes competing for CPU time > > to reclaim memory. That doesn't reclaim any faster and may be an > > unnecessary kill. > > ... > > - offer a way to wait for process termination so lmkd can tell when > > reclaim has finished and know when killing another process is > > appropriate > > Should be pretty easy with something like this: Yeah, that's in the spirit of what I was suggesting, but there are lot of edge cases around how to get that data out efficiently and PID reuse (it's a real issue--often the Android apps that are causing memory pressure are also constantly creating/destroying threads). I believe procfds or a similar mechanism will be a good solution to this. _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
