On Tue, 2 Apr 2013, Lin Feng wrote: > > so, again, if I understand correctly, thp should tune the naturally aligned maps, such as generated by mmap()/malloc(), > > make such maps 'hugepagesize' aligned if the maps or vma is equal and greater than 'hugepagesize', doesn't it? > > We may gain performance improving from this. > To attain the maximum number of hugepages, you would naturally want to ensure that the mappings are done aligned to 2MB; for very large allocations, missing one or two hugepages typically won't hurt performance much. posix_memalign() is the best way of doing this which just wraps mmap() for the needed alignment. More interesting is creating your own custom malloc() that allocates in 2MB aligned chunks, if possible, and uses 2MB aligned arenas for its own metadata. If you do that for malloc(), then you'll only need to make code that does its own mmap()s to use posix_memalign(). -- 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>