On Sun, Nov 2, 2014 at 6:15 AM, Johannes Weiner <hannes@xxxxxxxxxxx> wrote: > Memory cgroups used to have 5 per-page pointers. To allow users to > disable that amount of overhead during runtime, those pointers were > allocated in a separate array, with a translation layer between them > and struct page. > > There is now only one page pointer remaining: the memcg pointer, that > indicates which cgroup the page is associated with when charged. The > complexity of runtime allocation and the runtime translation overhead > is no longer justified to save that *potential* 0.19% of memory. With > CONFIG_SLUB, page->mem_cgroup actually sits in the doubleword padding > after the page->private member and doesn't even increase struct page, > and then this patch actually saves space. Remaining users that care > can still compile their kernels without CONFIG_MEMCG. > > text data bss dec hex filename > 8828345 1725264 983040 11536649 b00909 vmlinux.old > 8827425 1725264 966656 11519345 afc571 vmlinux.new > > Signed-off-by: Johannes Weiner <hannes@xxxxxxxxxxx> Great! Never thought I'd see this. =) Acked-by: Konstantin Khlebnikov <koct9i@xxxxxxxxx> > --- > include/linux/memcontrol.h | 6 +- > include/linux/mm_types.h | 5 + > include/linux/mmzone.h | 12 -- > include/linux/page_cgroup.h | 53 -------- > init/main.c | 7 - > mm/memcontrol.c | 124 +++++------------ > mm/page_alloc.c | 2 - > mm/page_cgroup.c | 319 -------------------------------------------- > 8 files changed, 41 insertions(+), 487 deletions(-) > > diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h > index d4575a1d6e99..dafba59b31b4 100644 > 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> -- 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>