mm/damon/usage.rst

1 .. SPDX-License-Identifier: GPL-2.0
9 - *DAMON user space tool.*
11   system administrators who want a just-working human-friendly interface.
12   Using this, users can use the DAMON’s major features in a human-friendly way.
16 - *sysfs interface.*
23 - *Kernel Space Programming Interface.*
44     # echo 1 > kdamonds/nr_kdamonds && echo 1 > kdamonds/0/contexts/nr_contexts
46     # echo 1 > kdamonds/0/contexts/0/targets/nr_targets
51 ---------------
54 figure, parents-children relations are represented with indentations, each
58 .. parsed-literal::
99 ----
109 ---------
116 child directories named ``0`` to ``N-1``.  Each directory represents each
122 -------------
132 - ``on``: Start running.
133 - ``off``: Stop running.
134 - ``commit``: Read the user inputs in the sysfs files except ``state`` file
136 - ``update_tuned_intervals``: Update the contents of ``sample_us`` and
137   ``aggr_us`` files of the kdamond with the auto-tuning applied ``sampling
141 - ``commit_schemes_quota_goals``: Read the DAMON-based operation schemes'
143 - ``update_schemes_stats``: Update the contents of stats files for each
144   DAMON-based operation scheme of the kdamond.  For details of the stats,
146 - ``update_schemes_tried_regions``: Update the DAMON-based operation scheme
147   action tried regions directory for each DAMON-based operation scheme of the
148   kdamond.  For details of the DAMON-based operation scheme action tried
151 - ``update_schemes_tried_bytes``: Update only ``.../tried_regions/total_bytes``
153 - ``clear_schemes_tried_regions``: Clear the DAMON-based operating scheme
154   action tried regions directory for each DAMON-based operation scheme of the
156 - ``update_schemes_effective_quotas``: Update the contents of
157   ``effective_bytes`` files for each DAMON-based operation scheme of the
168 ----------------------
172 ``0`` to ``N-1``.  Each directory represents each monitoring context (refer to
175 ``0`` or ``1`` can be written to the file.
180 -------------
190 ``avail_operations`` file.  Based on the kernel configuration, the file will
202 ------------------------------
211 (``update_us``) exist.  You can set and get the values in micro-seconds by
214 Under ``nr_regions`` directory, two files for the lower-bound and upper-bound
225 -------------------------------------------------------
229 Under the directory, four files for the auto-tuning control, namely
236 names.  The tuning starts with the user-set ``sample_us`` and ``aggr_us``.  The
237 tuning-applied current values of the two intervals can be read from the
244 ---------------------
248 to ``N-1``.  Each directory represents each monitoring target.
253 ------------
265 -------------------
278 to ``N-1``.  Each directory represents each initial monitoring target region.
283 ------------
290 be equal or smaller than ``start`` of directory ``N+1``.
295 ---------------------
297 The directory for DAMON-based Operation Schemes (:ref:`DAMOS
303 to ``N-1``.  Each directory represents each DAMON-based operation scheme.
308 ------------
330 ---------------------------
333 <damon_design_damos_access_pattern>` of the given DAMON-based operation scheme.
345 -------------------
348 DAMON-based operation scheme.
364 transformed size quota and user-specified size quota, smaller one is applied.
365 Based on the user-specified :ref:`goal <sysfs_schemes_quota_goals>`, the
376 in per-thousand unit by writing the values to the three files under the
382 -------------------------
385 <damon_design_damos_quotas_auto_tuning>` of the given DAMON-based operation
390 to ``N-1``.  Each directory represents each goal and current achievement.
395 parameters for the quota auto-tuning goals that specified on the :ref:`design
404 -----------------------
407 given DAMON-based operation scheme.
417  - none: Ignore the watermarks
418  - free_mem_rate: System's free memory rate (per thousand)
425 -----------------------------------
428 DAMON-based operation scheme.
443 to ``N-1``.  Each directory represents each filter.  The filters are evaluated
455 address of the range (open-ended interval) to ``addr_start`` and ``addr_end``
467 For example, below restricts a DAMOS action to be applied to only non-anonymous
477     echo memcg > 1/type
478     echo /having_care_already > 1/memcg_path
479     echo Y > 1/matching
480     echo N > 1/allow
490 ------------------
506 --------------------------
529 and query-like efficient data access monitoring results retrievals.  For the
536 ------------------
540 show the properties of the region that corresponding DAMON-based operation
549 10ms per second, and also don't page out more than 1GiB per second.  Under the
557     # echo 1 > kdamonds/nr_kdamonds; echo 1 > kdamonds/0/contexts/nr_contexts;
558     # echo 1 > kdamonds/0/contexts/0/schemes/nr_schemes
594 provides the monitoring results for regions that each DAMON-based Operation
598 :ref:`pattern <damon_design_damos_access_pattern>` based query-like efficient
605     # perf record -e damon:damon_aggregated &
610 …7] 79357.842179: damon:damon_aggregated: target_id=0 nr_regions=11 122509119488-135708762112: 0 864
617 for the target.  The eighth field (``X-Y:``) shows the start (``X``) and end
628 …os_before_apply: ctx_idx=0 scheme_idx=0 target_idx=0 nr_regions=11 121932607488-135128711168: 0 136
631 Each line of the output represents each monitoring region that each DAMON-based