diff options
| author | Huang Ying <ying.huang@intel.com> | 2018-05-09 16:23:41 +0800 |
|---|---|---|
| committer | Jonathan Corbet <corbet@lwn.net> | 2018-05-10 15:42:42 -0600 |
| commit | 8d420f6c27c530e25c057a59575e193dd62bb743 (patch) | |
| tree | 09bbd1523ecafee50c5a1bd8f5094afee7ec02a7 /Documentation/vm | |
| parent | 9167b942d53c96e7ddeb59ee0f84930955d7b682 (diff) | |
mm, THP, doc: Add document for thp_swpout/thp_swpout_fallback
Add document for newly added thp_swpout, thp_swpout_fallback fields in
/proc/vmstat.
Signed-off-by: "Huang, Ying" <ying.huang@intel.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Diffstat (limited to 'Documentation/vm')
| -rw-r--r-- | Documentation/vm/transhuge.rst | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/Documentation/vm/transhuge.rst b/Documentation/vm/transhuge.rst index 569d182cc973..2c6867fca6ff 100644 --- a/Documentation/vm/transhuge.rst +++ b/Documentation/vm/transhuge.rst @@ -355,6 +355,15 @@ thp_zero_page_alloc_failed is incremented if kernel fails to allocate huge zero page and falls back to using small pages. +thp_swpout + is incremented every time a huge page is swapout in one + piece without splitting. + +thp_swpout_fallback + is incremented if a huge page has to be split before swapout. + Usually because failed to allocate some continuous swap space + for the huge page. + As the system ages, allocating huge pages may be expensive as the system uses memory compaction to copy data around memory to free a huge page for use. There are some counters in ``/proc/vmstat`` to help |