Docs/admin-guide/mm/damon/usage: clarify quotas and watermarks sysfs interface

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

Link: https://lkml.kernel.org/r/20230616191742.87531-7-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit is contained in:
SeongJae Park 2023-06-16 19:17:41 +00:00 committed by Andrew Morton
parent 01e08737da
commit 67c34f6c6a

View file

@ -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.