* [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.