On Mon, 2013-08-05 at 16:36 +0900, Joonsoo Kim wrote: > > Any mapping that doesn't use the reserved pool, not just > > MAP_NORESERVE. For example, if a process makes a MAP_PRIVATE mapping, > > then fork()s then the mapping is instantiated in the child, that will > > not draw from the reserved pool. > > > > > Should we ensure them to allocate the last hugepage? > > > They map a region with MAP_NORESERVE, so don't assume that their requests > > > always succeed. > > > > If the pages are available, people get cranky if it fails for no > > apparent reason, MAP_NORESERVE or not. They get especially cranky if > > it sometimes fails and sometimes doesn't due to a race condition. > > Hello, > > Hmm... Okay. I will try to implement another way to protect race condition. > Maybe it is the best to use a table mutex :) > Anyway, please give me a time, guys. So another option is to take the mutex table patchset for now as it *does* improve things a great deal, then, when ready, get rid of the instantiation lock all together. Thanks, Davidlohr -- 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>