Add a flag which causes page-types to use the kernels's idle page
tracking to mark pages idle. As the tool already prints the idle flag
if set, subsequent runs will show which pages have been accessed since
last run.
[akpm@linux-foundation.org: simplify mark_page_idle()]
[chansen3@cisco.com: reorganize mark_page_idle() logic, add docs]
Link: http://lkml.kernel.org/r/20180706172237.21691-1-chansen3@cisco.com
Link: http://lkml.kernel.org/r/20180612153223.13174-1-chansen3@cisco.com
Signed-off-by: Christian Hansen <chansen3@cisco.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add a new flag that will read kpagecount for each PFN and print out the
number of times the page is mapped along with the flags in the listing
view.
This information is useful in understanding and optimizing memory usage.
Identifying pages which are not shared allows us to focus on adjusting
the memory layout or access patterns for the sole owning process.
Knowing the number of processes that share a page tells us how many
other times we must make the same adjustments or how many processes to
potentially disable.
Truncated sample output:
voffset map-cnt offset len flags
561a3591e 1 15fe8 1 ___U_lA____Ma_b___________________________
561a3591f 1 2b103 1 ___U_lA____Ma_b___________________________
561a36ca4 1 2cc78 1 ___U_lA____Ma_b___________________________
7f588bb4e 14 2273c 1 __RU_lA____M______________________________
[akpm@linux-foundation.org: coding-style fixes]
[chansen3@cisco.com: add documentation, tweak whitespace]
Link: http://lkml.kernel.org/r/20180705181204.5529-1-chansen3@cisco.com
Link: http://lkml.kernel.org/r/20180612153205.12879-1-chansen3@cisco.com
Signed-off-by: Christian Hansen <chansen3@cisco.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The are terms that seem obvious to the mm developers, but may be somewhat
obscure for, say, less involved readers.
The concepts overview can be seen as an "extended glossary" that introduces
such terms to the readers of the kernel documentation.
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Now that the administrative information for transparent huge pages is
nicely separated, move it to its own page under the admin guide.
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
The document describes userspace API and as such it belongs to
Documentation/admin-guide/mm
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Several documents in Documentation/vm fit quite well into the "admin/user
guide" category. The documents that don't overload the reader with lots of
implementation details and provide coherent description of certain feature
can be moved to Documentation/admin-guide/mm.
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>