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>
Update DAMON design doc to explain the quota goal self-tuning, which can
be used by setting the goal's metric to metrics that kernel can
self-retrieve.
Link: https://lkml.kernel.org/r/20240219194431.159606-16-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.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>
The list of DAMON operation sets and their explanation, which may better
to be on design document, is written on the usage document. Move the
detail to design document and make the usage document only reference the
design document.
[sj@kernel.org: fix a typo on a reference link]
Link: https://lkml.kernel.org/r/20240221170852.55529-2-sj@kernel.org
Link: https://lkml.kernel.org/r/20240217005842.87348-4-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>
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>
The execution model and data structures section at the end of the design
document is briefly explaining how DAMON works overall. Knowing that
first may help better drawing the overall picture. It may also help
better understanding following detailed sections. Move it to the
beginning of the document.
Link: https://lkml.kernel.org/r/20231213190338.54146-4-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>
Document the DAMOS quota auto tuning feature on the design document.
Link: https://lkml.kernel.org/r/20231130023652.50284-8-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Brendan Higgins <brendanhiggins@google.com>
Cc: David Gow <davidgow@google.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The explanation of kdamond and context is duplicated in the design and
the usage documents. Replace that in the usage with links to those in
the design document.
Link: https://lkml.kernel.org/r/20230907022929.91361-8-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The design document is not explaining about the concept of kdamond and
the DAMON context, while usage document does. Those concept explanation
should be in the design document, and usage document should link those.
Add a section for those.
Link: https://lkml.kernel.org/r/20230907022929.91361-7-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The example of the section for damon_aggregated tracepoint is not
explaining how the output looks like, and how it can be interpreted.
Add it.
Link: https://lkml.kernel.org/r/20230907022929.91361-6-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The design document is explaining about the access tracking mechanism
and the access rate counter (nr_accesses), but not directly mentions the
name. Add a sentence for making it clear.
Link: https://lkml.kernel.org/r/20230907022929.91361-5-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Update DAMON design document's DAMOS filters section for address range
DAMOS filters. Because address range filters are handled by the core
layer and it makes difference in schemes tried regions and schemes
statistics, clearly describe it.
Link: https://lkml.kernel.org/r/20230802214312.110532-6-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Brendan Higgins <brendanhiggins@google.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The background and concept of DAMOS is redundantly documented, in the
design document and the usage document. Replace the duplicated ones in
usage document with links to the design document.
Link: https://lkml.kernel.org/r/20230616191742.87531-6-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>
Patch series "Docs/{mm,admin-guide}damon: update design and usage docs".
Update DAMON design and usage documents for outdated and unnecessarily
duplicated parts.
This patch (of 7):
The 'age' of each region in DAMON monitoring results is an important
concept for both monitoring part and DAMOS. And DAMOS section of the
design document is mentioning it. However, the age itself is not
explained in the document. Add a section for that.
Link: https://lkml.kernel.org/r/20230616191742.87531-1-sj@kernel.org
Link: https://lkml.kernel.org/r/20230616191742.87531-2-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>
Add a section for covering DAMON modules layer to the design document.
Link: https://lkml.kernel.org/r/20230525214314.5204-11-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>
Add a section covering the API of DAMON core layer on the design document.
Link: https://lkml.kernel.org/r/20230525214314.5204-10-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>
Add sections for advanced features of DAMOS including quotas,
prioritization, watermarks, and filters of DAMOS on the design document.
Link: https://lkml.kernel.org/r/20230525214314.5204-9-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 is an important part of DAMON, but the design doc is not covering
it. Add sections for covering the basic part of DAMOS.
Link: https://lkml.kernel.org/r/20230525214314.5204-8-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>
Add overall desription of the interface and the relation between the Core
and the Modules layer under 'Overall Architecture' section.
Link: https://lkml.kernel.org/r/20230525214314.5204-7-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>
The 'Configurable Operations Set' section is a little bit outdated.
Update the text.
Link: https://lkml.kernel.org/r/20230525214314.5204-6-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 is describing only the operations set layer and
monitoring part of the core logic. Update the layout based on the DAMON's
layers, so that more parts of DAMON including DAMOS core logic and DAMON
modules can easily be added.
Link: https://lkml.kernel.org/r/20230525214314.5204-5-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>
The design doc is missing overall picture of DAMON. Add a section for
overall architeucture and layers.
Link: https://lkml.kernel.org/r/20230525214314.5204-4-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>
so it will be consistent with code mm directory and with
Documentation/admin-guide/mm and won't be confused with virtual machines.
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Suggested-by: Matthew Wilcox <willy@infradead.org>
Tested-by: Ira Weiny <ira.weiny@intel.com>
Acked-by: Jonathan Corbet <corbet@lwn.net>
Acked-by: Wu XiangCheng <bobwxc@email.cn>
Barry Song