.. SPDX-License-Identifier: GPL-2.0

========================== DAMON: Data Access MONitor

DAMON is a Linux kernel subsystem that provides a framework for data access monitoring and the monitoring results based system operations. The core monitoring :ref:mechanisms <damon_design_monitoring> of DAMON make it

• accurate (the monitoring output is useful enough for DRAM level memory management; It might not appropriate for CPU Cache levels, though),
• light-weight (the monitoring overhead is low enough to be applied online), and
• scalable (the upper-bound of the overhead is in constant range regardless of the size of target workloads).

Using this framework, therefore, the kernel can operate system in an access-aware fashion. Because the features are also exposed to the :doc:user space </admin-guide/mm/damon/index>, users who have special information about their workloads can write personalized applications for better understanding and optimizations of their workloads and systems.

For easier development of such systems, DAMON provides a feature called :ref:DAMOS <damon_design_damos> (DAMon-based Operation Schemes) in addition to the monitoring. Using the feature, DAMON users in both kernel and :doc:user spaces </admin-guide/mm/damon/index> can do access-aware system operations with no code but simple configurations.

.. toctree:: :maxdepth: 2

faq design api maintainer-profile

To utilize and control DAMON from the user-space, please refer to the administration :doc:guide </admin-guide/mm/damon/index>.