From: SeongJae Park <sjpark@xxxxxxxxx> This commit documents the 'initial_regions' feature. Signed-off-by: SeongJae Park <sjpark@xxxxxxxxx> --- Documentation/admin-guide/mm/damon/usage.rst | 34 ++++++++++++++++++++ 1 file changed, 34 insertions(+) diff --git a/Documentation/admin-guide/mm/damon/usage.rst b/Documentation/admin-guide/mm/damon/usage.rst index 2f5b67302094..24f1b05a859a 100644 --- a/Documentation/admin-guide/mm/damon/usage.rst +++ b/Documentation/admin-guide/mm/damon/usage.rst @@ -329,6 +329,40 @@ having pids 42 and 4242 as the processes to be monitored and check it again:: Note that setting the pids doesn't start the monitoring. +Initial Monitoring Target Regions +--------------------------------- + +DAMON automatically sets and updates the monitoring target regions so that +entire memory mappings of target processes can be covered. However, users +might want to limit the monitoring region to specific address ranges, such as +the heap, the stack, or specific file-mapped area. Or, some users might know +the initial access pattern of their workloads and therefore want to set optimal +initial regions for the 'adaptive regions adjustment'. + +In such cases, users can explicitly set the initial monitoring target regions +as they want, by writing proper values to the ``init_regions`` file. Each line +of the input should represent one region in below form.:: + + <pid> <start address> <end address> + +The ``pid`` should be already in ``pids`` file, and the regions should be +passed in address order. For example, below commands will set a couple of +address ranges, ``1-100`` and ``100-200`` as the initial monitoring target +region of process 42, and another couple of address ranges, ``20-40`` and +``50-100`` as that of process 4242.:: + + # cd <debugfs>/damon + # echo "42 1 100 + 42 100 200 + 4242 20 40 + 4242 50 100" > init_regions + +Note that this sets the initial monitoring target regions only. DAMON will +automatically updates the boundary of the regions after one ``regions update +interval``. Therefore, users should set the ``regions update interval`` large +enough. + + Record ------ -- 2.17.1
