All of lore.kernel.org
 help / color / mirror / Atom feed
* [merged mm-stable] docs-mm-damon-design-document-data-attributes-monitoring.patch removed from -mm tree
@ 2026-06-02 22:25 Andrew Morton
  0 siblings, 0 replies; only message in thread
From: Andrew Morton @ 2026-06-02 22:25 UTC (permalink / raw)
  To: mm-commits, vbabka, surenb, shuah, rppt, rostedt, mhocko,
	mhiramat, mathieu.desnoyers, ljs, liam, david, corbet, sj, akpm


The quilt patch titled
     Subject: Docs/mm/damon/design: document data attributes monitoring
has been removed from the -mm tree.  Its filename was
     docs-mm-damon-design-document-data-attributes-monitoring.patch

This patch was dropped because it was merged into the mm-stable branch
of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

------------------------------------------------------
From: SeongJae Park <sj@kernel.org>
Subject: Docs/mm/damon/design: document data attributes monitoring
Date: Mon, 18 May 2026 16:41:08 -0700

Update DAMON design document for newly added data attributes monitoring
feature.

Link: https://lore.kernel.org/20260518234119.97569-21-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: David Hildenbrand <david@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Liam R. Howlett <liam@infradead.org>
Cc: Lorenzo Stoakes <ljs@kernel.org>
Cc: "Masami Hiramatsu (Google)" <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 Documentation/mm/damon/design.rst |   37 ++++++++++++++++++++++++++++
 1 file changed, 37 insertions(+)

--- a/Documentation/mm/damon/design.rst~docs-mm-damon-design-document-data-attributes-monitoring
+++ a/Documentation/mm/damon/design.rst
@@ -276,6 +276,43 @@ interval``, DAMON checks if the region's
 (``nr_accesses``) has significantly changed.  If so, the counter is reset to
 zero.  Otherwise, the counter is increased.
 
+Data Attributes Monitoring
+~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Data access pattern is only one type of data attributes.  In some use cases,
+users need to know more data attributes information.  For example, users may
+need to know how much of a given hot or cold memory region is backed by
+anonymous pages, or belong to a specific cgroup.  For such use case, data
+attributes monitoring feature is provided.
+
+Using the feature, users can register data attributes of their interest to the
+DAMON :ref:`context <damon_design_execution_model_and_data_structures>`.  The
+registration is made by specifying a probe per attribute.  Each of the probe
+specifies a rule to determine if a given memory region has the related
+attribute.  The rule is constructed with multiple filters.  The filters work
+same to :ref:`DAMOS filters <damon_design_damos_filters>` except the supported
+filter types.  Currently only ``anon`` filter type is supported for data
+attributes monitoring.
+
+If such probes are registered, DAMON executes the probes for each region's
+sampling memory when it does the access :ref:`sampling
+<damon_design_region_based_sampling>`.  The number of samples that identified
+as having the data attribute (hitting the probe) per :ref:`aggregation interval
+<damon_design_monitoring>` is accounted in a per-region per-probe counter.
+Users can therefore know how much of a given DAMON region has a specific data
+attribute by reading the per-region per-probe probe hits counter after each
+aggregation interval.
+
+This is a sampling based mechanism.  Hence, it is lightweight but the output
+may include some measurement errors.  The output should be used with good
+understanding of statistics.
+
+Another way to do this for higher accuracy is using :ref:`DAMOS filter
+<damon_design_damos_filters>` with ``stat`` :ref:`action
+<damon_design_damos_action>` and ``sz_ops_filter_passed`` :ref:`stat
+<damon_design_damos_stat>`.  This approach provides the data attributes
+information in page level.  But, because it is operated in page level, the
+overhead is proportional to the size of the memory.
 
 Dynamic Target Space Updates Handling
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
_

Patches currently in -mm which might be from sj@kernel.org are

mm-damon-reclaim-handle-ctx-allocation-failure.patch
mm-damonn-lru_sort-handle-ctx-allocation-failure.patch
maintainers-add-testing-abi-documents-for-mm.patch


^ permalink raw reply	[flat|nested] only message in thread

only message in thread, other threads:[~2026-06-02 22:25 UTC | newest]

Thread overview: (only message) (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2026-06-02 22:25 [merged mm-stable] docs-mm-damon-design-document-data-attributes-monitoring.patch removed from -mm tree Andrew Morton

This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.