From cf8496ea8020792ea32d0fbec0c140d8de93011a Mon Sep 17 00:00:00 2001 From: Shaohua Li Date: Wed, 3 May 2017 14:52:42 -0700 Subject: proc: show MADV_FREE pages info in smaps Show MADV_FREE pages info of each vma in smaps. The interface is for diganose or monitoring purpose, userspace could use it to understand what happens in the application. Since userspace could dirty MADV_FREE pages without notice from kernel, this interface is the only place we can get accurate accounting info about MADV_FREE pages. [mhocko@kernel.org: update Documentation/filesystems/proc.txt] Link: http://lkml.kernel.org/r/89efde633559de1ec07444f2ef0f4963a97a2ce8.1487965799.git.shli@fb.com Signed-off-by: Shaohua Li Acked-by: Johannes Weiner Acked-by: Minchan Kim Acked-by: Michal Hocko Acked-by: Hillf Danton Cc: Hugh Dickins Cc: Rik van Riel Cc: Mel Gorman Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Documentation/filesystems/proc.txt | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'Documentation/filesystems') diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt index 9036dbf16156..4cddbce85ac9 100644 --- a/Documentation/filesystems/proc.txt +++ b/Documentation/filesystems/proc.txt @@ -413,6 +413,7 @@ Private_Clean: 0 kB Private_Dirty: 0 kB Referenced: 892 kB Anonymous: 0 kB +LazyFree: 0 kB AnonHugePages: 0 kB ShmemPmdMapped: 0 kB Shared_Hugetlb: 0 kB @@ -442,6 +443,11 @@ accessed. "Anonymous" shows the amount of memory that does not belong to any file. Even a mapping associated with a file may contain anonymous pages: when MAP_PRIVATE and a page is modified, the file page is replaced by a private anonymous copy. +"LazyFree" shows the amount of memory which is marked by madvise(MADV_FREE). +The memory isn't freed immediately with madvise(). It's freed in memory +pressure if the memory is clean. Please note that the printed value might +be lower than the real value due to optimizations used in the current +implementation. If this is not desirable please file a bug report. "AnonHugePages" shows the ammount of memory backed by transparent hugepage. "ShmemPmdMapped" shows the ammount of shared (shmem/tmpfs) memory backed by huge pages. -- cgit v1.2.3