On Fri, 2013-06-14 at 15:47 -0700, Michel Lespinasse wrote: > On Fri, Jun 14, 2013 at 3:31 PM, Davidlohr Bueso <davidlohr.bueso@xxxxxx> wrote: > > A few ideas that come to mind are avoiding taking the ->wait_lock and > > avoid dealing with waiters when doing the optimistic spinning (just like > > mutexes do). > > > > I agree that we should first deal with the optimistic spinning before > > adding the MCS complexity. > > Maybe it would be worth disabling the MCS patch in mutex and comparing > that to the rwsem patches ? Just to make sure the rwsem performance > delta isn't related to that. > I've tried to back out the MCS patch. In fact, for exim, it is about 1% faster without MCS. So the better performance of mutex I saw was not due to MCS. Thanks for the suggestion. Tim -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>