diff options
| author | SJ Park <sj@kernel.org> | 2026-07-10 06:46:46 -0700 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2026-08-04 19:18:52 -0700 |
| commit | f10489d2ef8e76bbb3eb78c5b963abae3a4a8dc9 (patch) | |
| tree | faaa244107b48641d23d08d1dd3910464fcac08b | |
| parent | 2430a8d5172c257158091368b81e27fdce535475 (diff) | |
Docs/mm/damon/design: document attrs-only monitoring
Update DAMON design document for the attributes only monitoring mode.
Link: https://lore.kernel.org/20260710134651.18084-18-sj@kernel.org
Signed-off-by: SJ 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: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
| -rw-r--r-- | Documentation/mm/damon/design.rst | 20 |
1 files changed, 20 insertions, 0 deletions
diff --git a/Documentation/mm/damon/design.rst b/Documentation/mm/damon/design.rst index 457d6e8bc787..6d79e7d69be8 100644 --- a/Documentation/mm/damon/design.rst +++ b/Documentation/mm/damon/design.rst @@ -316,6 +316,26 @@ Another way to do this for higher accuracy is using :ref:`DAMOS filter information in page level. But, because it is operated in page level, the overhead is proportional to the size of the memory. +Data Attributes-only Monitoring +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +Data access is the primary monitoring information for DAMON. Hence it +:ref:`adjusts <damon_design_data_attrs_monitoring>` regions using the access +:ref:`counter <damon_design_region_based_sampling>` (``nr_accesses``). In some +use cases, however, users may want some of :ref:`attributes +<damon_design_data_attrs_monitoring>` to be the primary information. + +Data attributes-only monitoring mode supports this use case. For the mode, +each attribute probe has their priority weight value. Users can describe by +what combination of the attributes the primary information is decided, by +setting the priority weight value. If the total sum of the weights is not +zero, the mode is enabled. The regions adjustment mechanism uses the weighted +sum of the :ref:`probe hit counts <damon_design_data_attrs_monitoring>` instead +of ``nr_accesses`` in the case. When the mode is enabled, access monitoring is +automatically turned off. The access counter (``nr_accesses``) will always be +zero and not updated. Hence the mode is called Data Attributes "only" +monitoring. + Dynamic Target Space Updates Handling ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ |