From a1a650dc46a625d224d4a0360dc115cedea929f5 Mon Sep 17 00:00:00 2001 From: SeongJae Park Date: Fri, 17 Oct 2025 14:27:00 -0700 Subject: [PATCH] Docs/mm/damon/design: document DAMOS_QUOTA_NODE_MEMCG_{USED,FREE}_BP Update design doc for the newly added two DAMOS quota auto-tuning target goal metrics, DAMOS_QUOTA_NODE_MEMCG_{USED,FREE}_BP. Link: https://lkml.kernel.org/r/20251017212706.183502-9-sj@kernel.org Signed-off-by: SeongJae Park Signed-off-by: Andrew Morton --- Documentation/mm/damon/design.rst | 21 +++++++++++++++------ 1 file changed, 15 insertions(+), 6 deletions(-) diff --git a/Documentation/mm/damon/design.rst b/Documentation/mm/damon/design.rst index 80354f4f42ba..b54925ea78e9 100644 --- a/Documentation/mm/damon/design.rst +++ b/Documentation/mm/damon/design.rst @@ -564,9 +564,9 @@ aggressiveness (the quota) of the corresponding scheme. For example, if DAMOS is under achieving the goal, DAMOS automatically increases the quota. If DAMOS is over achieving the goal, it decreases the quota. -The goal can be specified with four parameters, namely ``target_metric``, -``target_value``, ``current_value`` and ``nid``. The auto-tuning mechanism -tries to make ``current_value`` of ``target_metric`` be same to +The goal can be specified with five parameters, namely ``target_metric``, +``target_value``, ``current_value``, ``nid`` and ``path``. The auto-tuning +mechanism tries to make ``current_value`` of ``target_metric`` be same to ``target_value``. - ``user_input``: User-provided value. Users could use any metric that they @@ -581,9 +581,18 @@ tries to make ``current_value`` of ``target_metric`` be same to set by users at the initial time. In other words, DAMOS does self-feedback. - ``node_mem_used_bp``: Specific NUMA node's used memory ratio in bp (1/10,000). - ``node_mem_free_bp``: Specific NUMA node's free memory ratio in bp (1/10,000). - -``nid`` is optionally required for only ``node_mem_used_bp`` and -``node_mem_free_bp`` to point the specific NUMA node. +- ``node_memcg_used_bp``: Specific cgroup's node used memory ratio for a + specific NUMA node, in bp (1/10,000). +- ``node_memcg_free_bp``: Specific cgroup's node unused memory ratio for a + specific NUMA node, in bp (1/10,000). + +``nid`` is optionally required for only ``node_mem_used_bp``, +``node_mem_free_bp``, ``node_memcg_used_bp`` and ``node_memcg_free_bp`` to +point the specific NUMA node. + +``path`` is optionally required for only ``node_memcg_used_bp`` and +``node_memcg_free_bp`` to point the path to the cgroup. The value should be +the path of the memory cgroup from the cgroups mount point. To know how user-space can set the tuning goal metric, the target value, and/or the current value via :ref:`DAMON sysfs interface `, refer to -- 2.51.0