On Mon, 2013-07-29 at 15:18 +0900, Joonsoo Kim wrote: > On Fri, Jul 26, 2013 at 07:27:23AM -0700, Davidlohr Bueso wrote: > > This patchset attempts to reduce the amount of contention we impose > > on the hugetlb_instantiation_mutex by replacing the global mutex with > > a table of mutexes, selected based on a hash. The original discussion can > > be found here: http://lkml.org/lkml/2013/7/12/428 > > Hello, Davidlohr. > > I recently sent a patchset which remove the hugetlb_instantiation_mutex > entirely ('mm, hugetlb: remove a hugetlb_instantiation_mutex'). > This patchset can be found here: https://lkml.org/lkml/2013/7/29/54 > > If possible, could you review it and test it whether your problem is > disappered with it or not? This patchset applies on top of https://lkml.org/lkml/2013/7/22/96 "[PATCH v2 00/10] mm, hugetlb: clean-up and possible bug fix", right? AFAIK those changes are the ones Andrew picked up a few weeks ago and are now in linux-next, right? I was able to apply those just fine, but couldn't apply your 'remove a hugetlb_instantiation_mutex series' (IIRC pach 1/18 failed). I guess you'll send out a v2 anyway so I'll wait until then. In any case I'm not seeing an actual performance issue with the hugetlb_instantiation_mutex, all I noticed was that under large DB workloads that make use of hugepages, such as Oracle, this lock becomes quite hot during the first few minutes of startup, which makes sense in the fault path it is contended. So I'll try out your patches, but, in this particular case, I just cannot compare with the lock vs without the lock situations. 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>