* nishimura@xxxxxxxxxxxxxxxxx <nishimura@xxxxxxxxxxxxxxxxx> [2010-03-10 10:43:09]: > > Please please measure the performance overhead of this change. > > > > here. > > > > > > > > I made a patch below and measured the time(average of 10 times) of kernel build > > > > > > > on tmpfs(make -j8 on 8 CPU machine with 2.6.33 defconfig). > > > > > > > > > > > > > > <before> > > > > > > > - root cgroup: 190.47 sec > > > > > > > - child cgroup: 192.81 sec > > > > > > > > > > > > > > <after> > > > > > > > - root cgroup: 191.06 sec > > > > > > > - child cgroup: 193.06 sec > > > > > > > > > <after2(local_irq_save/restore)> > - root cgroup: 191.42 sec > - child cgroup: 193.55 sec > > hmm, I think it's in error range, but I can see a tendency by testing several times > that it's getting slower as I add additional codes. Using local_irq_disable()/enable() > except in mem_cgroup_update_file_mapped(it can be the only candidate to be called > with irq disabled in future) might be the choice. > Error range would depend on things like standard deviation and repetition. It might be good to keep update_file_mapped and see the impact. My concern is with large systems, the difference might be larger. -- Three Cheers, Balbir -- 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/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>