On what DAMON layer a DAMOS filter is handled is important to expect in
what order filters will be evaluated. Re-organize the DAMOS filter types
list on the design doc to categorize types based on the handling layer, to
let users more easily understand the handling order.
Link: https://lkml.kernel.org/r/20250218223708.53437-6-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>
If an element of memory matches a DAMOS filter, filters that installed
after that get no chance to make any effect to the element. Hence in what
order DAMOS filters are handled is important, if both allow filters and
reject filters are used together.
The ordering is affected by both the installation order and which layter
the filters are handled. The design document is not clearly documenting
the latter part. Clarify it on the design doc.
Link: https://lkml.kernel.org/r/20250218223708.53437-5-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>
DAMON sysfs usage doc is describing DAMOS filter type names and their
meanings in short. The design doc is providing the short meaning and
detailed descriptions, too. This is unnecessary duplicates and confuses
where to document new DAMOS filter types and features. Move the details
from usage to design doc.
Link: https://lkml.kernel.org/r/20250218223708.53437-4-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>
Patch series "Docs/mm/damon: misc DAMOS filters documentation fixes and
improves".
Fix and improve DAMOS filters documentation by fixing a copy-paste typo,
adding hugepage_size filter documentation on design doc, moving logic
details from usage to design, clarify DAMOS filters handling sequence
based on handling layer, and re-organizing the filters type list for
easier understanding of the handling sequence.
This patch (of 5):
The link from DAMOS filters design doc to usage doc has a typo calling
filters as watermarks. Fix it.
Link: https://lkml.kernel.org/r/20250218223708.53437-1-sj@kernel.org
Link: https://lkml.kernel.org/r/20250218223708.53437-2-sj@kernel.org
Fixes: d31f5626a0 ("Docs/mm/damon/design: add links to sections of DAMON sysfs interface usage doc")
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Add a DAMON monitoring intervals tuning example that contains output from
a demonstration of the guide on a real server workload system. The
example with real world numbers will help users better understanding the
guide instructions and what outputs they can expect and verify. Those
will again help finding the rooms for improvements on the guide.
Link: https://lkml.kernel.org/r/20250110185232.54907-3-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Honggyu Kim <honggyu.kim@sk.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Yunjeong Mun <yunjeong.mun@sk.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "Docs/damon/maintainer-profile: a couple of minor hotfixes".
DAMON maintainer-profile.rst file patches[1] that were merged into the
v6.12-rc1 have a couple of minor mistakes. Fix those.
[1] https://lore.kernel.org/20240826015741.80707-1-sj@kernel.org
This patch (of 2):
Links to external web pages on DAMON's maintainer-profile.rst are missing
'_' suffixes. As a result, rendered document is having only verbose URLs
that cannot be clicked. Fix those.
Also, update the link texts for git trees to contain the names of the
trees, for better readability and avoiding below Sphinx warning.
maintainer-profile.rst:4: WARNING: Duplicate explicit target name: "tree".
Link: https://lkml.kernel.org/r/20241011170154.70651-1-sj@kernel.org
Link: https://lkml.kernel.org/r/20241011170154.70651-2-sj@kernel.org
Fixes: 2e9b3d6e2e ("Docs/damon/maintainer-profile: add links in place")
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
'Programmable Modules' section provides high level descriptions of the
DAMON API-based kernel modules layer. But 'Modules' section, which is at
the end of the document, provides every detail about the layer including
that of 'Programmable Modules' section.
Since the brief summary of the layers at the beginning of the document has
a link to the 'Modules' section, browsing to the section is not that
difficult. Remove 'Programmable Modules' section in favor of 'Modules'
section and reducing duplicates.
Link: https://lkml.kernel.org/r/20240701192706.51415-7-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>
'Configurable Operations Set' section is for providing a description of
the pluggability of the operations set layer. Just after that,
'Operations Set Layer' section, which is dedicated for the entire things
of the layer, follows. The layout is odd, and some descriptions are
duplicated. Move 'Configurable Operations Set' section into 'Operations
Set Layer' and re-write some of the detailed descriptions.
Link: https://lkml.kernel.org/r/20240701192706.51415-6-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>
DAMON design document briefly explains the overall layers architecture
first, and then provides detailed explanations of each layer with
dedicated sections. Letting readers go directly to the detailed sections
for specific layers could help easy browsing of the not-very-short
document. Add links from the overall summary to the sections of details.
Link: https://lkml.kernel.org/r/20240701192706.51415-5-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>
Patch series "Docs/damon: minor fixups and improvements".
Fixup typos, clarify regions merging operation design with recent change,
add access pattern snapshot example use case, and improve readability of
the design document and subsystem documents index by
reorganizing/wordsmithing and adding links to other sections and/or
documents for easy browsing.
This patch (of 9):
Fix two typos. The first one is just a simple typo: s/accurach/accuracy/
The second one is made by the author being out of their mind. 'Region
Based Sampling' section of the doc is mistakenly calling the access
frequency counter of region as 'nr_regions'. Fix it with the correct
name, 'nr_accesses'.
Link: https://lkml.kernel.org/r/20240701192706.51415-1-sj@kernel.org
Link: https://lkml.kernel.org/r/20240701192706.51415-2-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>
DAMON bi-weekly community meetup series has continued since 2022-08-15 for
community members who prefer synchronous chat over asynchronous mails.
Recently I got some feedbacks about the series from a few people. They
told me the series is helpful for understanding of the project and
particiapting to the development, but it could be further better in terms
of the visibility. Based on that, I started sending meeting reminder for
every occurrence. For people who don't subscribe the mailing list,
however, adding an announcement on the official document could be helpful.
Document the series on DAMON maintainer's profile for the purpose.
Link: https://lkml.kernel.org/r/20240621163626.74815-3-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "Docs/mm/damon/maintaier-profile: document a mailing tool and
community meetup series", v2.
There is a mailing tool that developed and maintained by DAMON
maintainer aiming to support DAMON community. Also there are DAMON
community meetup series. Both are known to have rooms of improvements
in terms of their visibility. Document those on the maintainer's
profile document.
This patch (of 2):
Since DAMON was merged into mainline, I periodically received some
questions around DAMON's mailing lists based workflow. The workflow is
not different from the normal ones that well documented, but it is also
true that it is not always easy and familiar for everyone.
I personally overcame it by developing and using a simple tool, named
HacKerMaiL (hkml)[1]. Based on my experience, I believe it is matured
enough to be used for simple workflows like that of DAMON. Actually some
DAMON contributors and Linux kernel developers other than myself told me
they are using the tool.
As DAMON maintainer, I also believe helping new DAMON community members
onboarding to the worklow is one of the most important parts of my
responsibilities. For the reason, the tool is announced[2] to support
DAMON community. To further increasing the visibility of the fact,
document the tool and the support plan on DAMON maintainer's profile.
[1] https://github.com/damonitor/hackermail
[2] https://github.com/damonitor/hackermail/commit/3909dad91301
Link: https://lkml.kernel.org/r/20240621163626.74815-1-sj@kernel.org
Link: https://lkml.kernel.org/r/20240621163626.74815-2-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The doc needs a fix. As only in the case of virtual address, we are
calling madvise() with MADV_PAGEOUT. But in the case of physical address,
we are calling reclaim_pages() directly. MADV_PAGEOUT on virtual address
is much more aggresive to reclaim memory compared to reclaim_pages() on
paddr region. This patch removes the details so that the description can
apply to both cases. And we don't need to couple with the implementation
details.
Link: https://lkml.kernel.org/r/20240224224751.4673-1-21cnbao@gmail.com
Signed-off-by: Barry Song <v-songbaohua@oppo.com>
Reviewed-by: SeongJae Park <sj@kernel.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Design doc is aimed to have all concept level details, while the usage doc
is focused on only how the features can be used. Some details about
monitoring target regions construction is on the usage doc. Move the
details about the monitoring target regions construction differences for
DAMON operations set from the usage to the design doc.
Link: https://lkml.kernel.org/r/20240217005842.87348-5-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>
DAMOS operation actions are explained nearly twice on the DAMON usage
document, once for the sysfs interface, and then again for the debugfs
interface. Duplication is bad. Also it would better to keep this kind of
concept level details in design document and keep the usage document small
and focus on only the usage. Move the list to design document and update
usage document to reference it.
Link: https://lkml.kernel.org/r/20240217005842.87348-3-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>