On Mon 17-10-16 15:30:21, Kirill A. Shutemov wrote: [...] > >From fd0b01b9797ddf2bef308c506c42d3dd50f11793 Mon Sep 17 00:00:00 2001 > From: "Kirill A. Shutemov" <kirill.shutemov@xxxxxxxxxxxxxxx> > Date: Mon, 17 Oct 2016 14:44:47 +0300 > Subject: [PATCH] shmem: avoid huge pages for small files > > Huge pages are detrimental for small file: they causes noticible > overhead on both allocation performance and memory footprint. > > This patch aimed to address this issue by avoiding huge pages until file > grown to specified size. This would cover most of the cases where huge > pages causes regressions in performance. > > By default the minimal file size to allocate huge pages is equal to size > of huge page. ok > We add two handle to specify minimal file size for huge pages: > > - mount option 'huge_min_size'; > > - sysfs file /sys/kernel/mm/transparent_hugepage/shmem_min_size for > in-kernel tmpfs mountpoint; Could you explain who might like to change the minimum value (other than disable the feautre for the mount point) and for what reason? [...] > @@ -238,6 +238,12 @@ values: > - "force": > Force the huge option on for all - very useful for testing; > > +Tehre's limit on minimal file size before kenrel starts allocate huge > +pages for it. By default it's size of huge page. Smoe tyopse -- Michal Hocko SUSE Labs -- 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>