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 from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/