On Tue, 9 Nov 2010, Greg Thelen wrote: > >> > Adding the number of swap pages to the byte limit of a memory control > >> > group makes no sense. Convert the pages to bytes before adding them. > >> > > >> > The only user of this code is the OOM killer, and the way it is used > >> > means that the error results in a higher OOM badness value. Since the > >> > cgroup limit is the same for all tasks in the cgroup, the error should > >> > have no practical impact at the moment. > >> > > >> > But let's not wait for future or changing users to trip over it. > >> > >> Thanks for the fix. > >> > > > > Nice catch, but it's done in the opposite way: the oom killer doesn't use > > byte limits but page limits. So this needs to be > > > > (res_counter_read_u64(&memcg->res, RES_LIMIT) >> PAGE_SHIFT) + > > total_swap_pages; > > In -mm, the oom killer queries memcg for a byte limit using > mem_cgroup_get_limit(). The following is from > mem_cgroup_out_of_memory(): > > limit = mem_cgroup_get_limit(mem) >> PAGE_SHIFT; > Oops, I missed that. I think Johannes' patch is better because mem_cgroup_get_limit() may eventually be used elsewhere and the subsystem has byte granularity. Thanks! -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxxx For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom policy in Canada: sign http://dissolvethecrtc.ca/ Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>