[PATCH 6/7] Docs/admin-guide/mm/damon/usage: clarify quotas and watermarks sysfs interface

From: SeongJae Park
Date: Fri Jun 16 2023 - 15:22:58 EST


Explanation of DAMOS quotas and watermarks are not clearly explaining
the meaning and expectation of each file. Add more clarification for
those.

Signed-off-by: SeongJae Park <sj@xxxxxxxxxx>
---
Documentation/admin-guide/mm/damon/usage.rst | 11 +++++++++--
1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/Documentation/admin-guide/mm/damon/usage.rst b/Documentation/admin-guide/mm/damon/usage.rst
index ea6a5dc8930e..9d3ebd70772f 100644
--- a/Documentation/admin-guide/mm/damon/usage.rst
+++ b/Documentation/admin-guide/mm/damon/usage.rst
@@ -306,7 +306,8 @@ Under the ``access_pattern`` directory, three directories (``sz``,
``nr_accesses``, and ``age``) each having two files (``min`` and ``max``)
exist. You can set and get the access pattern for the given scheme by writing
to and reading from the ``min`` and ``max`` files under ``sz``,
-``nr_accesses``, and ``age`` directories, respectively.
+``nr_accesses``, and ``age`` directories, respectively. Note that the ``min``
+and the ``max`` form a closed interval.

schemes/<N>/quotas/
-------------------
@@ -320,7 +321,13 @@ Under ``quotas`` directory, three files (``ms``, ``bytes``,

You can set the ``time quota`` in milliseconds, ``size quota`` in bytes, and
``reset interval`` in milliseconds by writing the values to the three files,
-respectively. You can also set the :ref:`prioritization weights
+respectively. Then, DAMON tries to use only up to ``time quota`` milliseconds
+for applying the ``action`` to memory regions of the ``access_pattern``, and to
+apply the action to only up to ``bytes`` bytes of memory regions within the
+``reset_interval_ms``. Setting both ``ms`` and ``bytes`` zero disables the
+quota limits.
+
+You can also set the :ref:`prioritization weights
<damon_design_damos_quotas_prioritization>` for size, access frequency, and age
in per-thousand unit by writing the values to the three files under the
``weights`` directory.
--
2.25.1