Re: A question about transparent hugepages

From: Kirill A. Shutemov
Date: Thu Aug 04 2016 - 05:16:27 EST


On Thu, Aug 04, 2016 at 12:02:29PM +0800, zhong jiang wrote:
> according to the total_mapcount, Different process can map any subpages of the
> transparent hugepages. How it can happen to ?

For anonymous memory it can only happen over copy-on-write via fork() +
munmap() or something in one of the processes.

Now we have tmpfs/shmem with huge pages in mainline. In this case you can
map any subpage directly from file.

--
Kirill A. Shutemov