On Fri, 4 Oct 2013 15:02:15 -0400 Naoya Horiguchi <n-horiguchi@xxxxxxxxxxxxx> wrote: > Soft dirty bit allows us to track which pages are written since the > last clear_ref (by "echo 4 > /proc/pid/clear_refs".) This is useful > for userspace applications to know their memory footprints. > > Note that the kernel exposes this flag via bit[55] of /proc/pid/pagemap, > and the semantics is not a default one (scheduled to be the default in > the near future.) However, it shifts to the new semantics at the first > clear_ref, and the users of soft dirty bit always do it before utilizing > the bit, so that's not a big deal. Users must avoid relying on the bit > in page-types before the first clear_ref. Is Documentation/filesystems/proc.txt (around line 450) fully up to date here? -- 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>