diff options
| author | SeongJae Park <sj@kernel.org> | 2025-10-26 11:22:12 -0700 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2025-11-16 17:28:22 -0800 |
| commit | da8644a476f5af7d282e304daf43f5c78c0acf13 (patch) | |
| tree | ee5650ed552011b9e03cc8031230e34fd1af4845 /Documentation/admin-guide | |
| parent | 448666e418bfe456bbc629f978c8b6d6c5027212 (diff) | |
Docs/admin-guide/mm/damon/stat: document aggr_interval_us parameter
Commit cc7ceb1d14b0 ("mm/damon/stat: expose the current tuned aggregation
interval"), has introduced 'aggr_interval_us' parameter for DAMON_STAT.
But the new parameter is not yet documented. Document it on the usage
document for the module.
Link: https://lkml.kernel.org/r/20251026182216.118200-8-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: David Hildenbrand <david@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'Documentation/admin-guide')
| -rw-r--r-- | Documentation/admin-guide/mm/damon/stat.rst | 18 |
1 files changed, 17 insertions, 1 deletions
diff --git a/Documentation/admin-guide/mm/damon/stat.rst b/Documentation/admin-guide/mm/damon/stat.rst index 20f540a9d3d2..754f98d47617 100644 --- a/Documentation/admin-guide/mm/damon/stat.rst +++ b/Documentation/admin-guide/mm/damon/stat.rst @@ -10,6 +10,8 @@ on the system's entire physical memory using DAMON, and provides simplified access monitoring results statistics, namely idle time percentiles and estimated memory bandwidth. +.. _damon_stat_monitoring_accuracy_overhead: + Monitoring Accuracy and Overhead ================================ @@ -19,7 +21,9 @@ overhead minimum. It auto-tunes the intervals aiming 4 % of observable access events to be captured in each snapshot, while limiting the resulting sampling interval to be 5 milliseconds in minimum and 10 seconds in maximum. On a few production server systems, it resulted in consuming only 0.x % single CPU time, -while capturing reasonable quality of access patterns. +while capturing reasonable quality of access patterns. The tuning-resulting +intervals can be retrieved via ``aggr_interval_us`` :ref:`parameter +<damon_stat_aggr_interval_us>`. Interface: Module Parameters ============================ @@ -41,6 +45,18 @@ You can enable DAMON_STAT by setting the value of this parameter as ``Y``. Setting it as ``N`` disables DAMON_STAT. The default value is set by ``CONFIG_DAMON_STAT_ENABLED_DEFAULT`` build config option. +.. _damon_stat_aggr_interval_us: + +aggr_interval_us +---------------- + +Auto-tuned aggregation time interval in microseconds. + +Users can read the aggregation interval of DAMON that is being used by the +DAMON instance for DAMON_STAT. It is :ref:`auto-tuned +<damon_stat_monitoring_accuracy_overhead>` and therefore the value is +dynamically changed. + estimated_memory_bandwidth -------------------------- |