diff options
| author | SeongJae Park <sj@kernel.org> | 2025-10-26 11:22:13 -0700 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2025-11-16 17:28:22 -0800 |
| commit | f46dbea0d95668dbbaf0aaa5f2c3aabf8f4d8fda (patch) | |
| tree | dc81031c1e56a8c22f79db3a7b0fa4329f3aafab /Documentation/admin-guide | |
| parent | da8644a476f5af7d282e304daf43f5c78c0acf13 (diff) | |
Docs/admin-guide/mm/damon/stat: document negative idle time
Commit a983a26d5298 ("mm/damon/stat: expose negative idle time")
introduced the negative idle time feature for DAMON_STAT. But it is not
documented. Document it on the usage document.
Link: https://lkml.kernel.org/r/20251026182216.118200-9-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: David Hildenbrand <david@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'Documentation/admin-guide')
| -rw-r--r-- | Documentation/admin-guide/mm/damon/stat.rst | 15 |
1 files changed, 8 insertions, 7 deletions
diff --git a/Documentation/admin-guide/mm/damon/stat.rst b/Documentation/admin-guide/mm/damon/stat.rst index 754f98d47617..e5a5a2c4f803 100644 --- a/Documentation/admin-guide/mm/damon/stat.rst +++ b/Documentation/admin-guide/mm/damon/stat.rst @@ -74,12 +74,13 @@ memory_idle_ms_percentiles Per-byte idle time (milliseconds) percentiles of the system. DAMON_STAT calculates how long each byte of the memory was not accessed until -now (idle time), based on the current DAMON results snapshot. If DAMON found a -region of access frequency (nr_accesses) larger than zero, every byte of the -region gets zero idle time. If a region has zero access frequency -(nr_accesses), how long the region was keeping the zero access frequency (age) -becomes the idle time of every byte of the region. Then, DAMON_STAT exposes -the percentiles of the idle time values via this read-only parameter. Reading -the parameter returns 101 idle time values in milliseconds, separated by comma. +now (idle time), based on the current DAMON results snapshot. For regions +having access frequency (nr_accesses) larger than zero, how long the current +access frequency level was kept multiplied by ``-1`` becomes the idlee time of +every byte of the region. If a region has zero access frequency (nr_accesses), +how long the region was keeping the zero access frequency (age) becomes the +idle time of every byte of the region. Then, DAMON_STAT exposes the +percentiles of the idle time values via this read-only parameter. Reading the +parameter returns 101 idle time values in milliseconds, separated by comma. Each value represents 0-th, 1st, 2nd, 3rd, ..., 99th and 100th percentile idle times. |