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-rw-r--r--Documentation/mm/damon/design.rst24
1 files changed, 14 insertions, 10 deletions
diff --git a/Documentation/mm/damon/design.rst b/Documentation/mm/damon/design.rst
index 3b4ce873fa71..eaf52f3a9144 100644
--- a/Documentation/mm/damon/design.rst
+++ b/Documentation/mm/damon/design.rst
@@ -19,8 +19,8 @@ DAMON subsystem is configured with three layers including
interfaces for the user space, on top of the core layer.
-Configurable Layers
-===================
+Configurable Operations Set
+---------------------------
DAMON provides data access monitoring functionality while making the accuracy
and the overhead controllable. The fundamental access monitorings require
@@ -42,8 +42,8 @@ Also, if some architectures or devices support special optimized access check
primitives, those will be easily configurable.
-Reference Implementations of Address Space Specific Monitoring Operations
-=========================================================================
+Operations Set Layer
+====================
The monitoring operations are defined in two parts:
@@ -105,8 +105,12 @@ conflict with the reclaim logic using ``PG_idle`` and ``PG_young`` page flags,
as Idle page tracking does.
-Address Space Independent Core Mechanisms
-=========================================
+Core Logics
+===========
+
+
+Monitoring
+----------
Below four sections describe each of the DAMON core mechanisms and the five
monitoring attributes, ``sampling interval``, ``aggregation interval``,
@@ -115,7 +119,7 @@ regions``.
Access Frequency Monitoring
----------------------------
+~~~~~~~~~~~~~~~~~~~~~~~~~~~
The output of DAMON says what pages are how frequently accessed for a given
duration. The resolution of the access frequency is controlled by setting
@@ -142,7 +146,7 @@ size of the target workload grows.
Region Based Sampling
----------------------
+~~~~~~~~~~~~~~~~~~~~~
To avoid the unbounded increase of the overhead, DAMON groups adjacent pages
that assumed to have the same access frequencies into a region. As long as the
@@ -159,7 +163,7 @@ assumption is not guaranteed.
Adaptive Regions Adjustment
----------------------------
+~~~~~~~~~~~~~~~~~~~~~~~~~~~
Even somehow the initial monitoring target regions are well constructed to
fulfill the assumption (pages in same region have similar access frequencies),
@@ -178,7 +182,7 @@ keeping the bounds users set for their trade-off.
Dynamic Target Space Updates Handling
--------------------------------------
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
The monitoring target address range could dynamically changed. For example,
virtual memory could be dynamically mapped and unmapped. Physical memory could