Documentation/ABI/testing/sysfs-kernel-mm-damon

Source file repositories/reference/linux-study-clean/Documentation/ABI/testing/sysfs-kernel-mm-damon

File Facts

System
Linux kernel
Corpus path
Documentation/ABI/testing/sysfs-kernel-mm-damon
Extension
[no extension]
Size
27073 bytes
Lines
604
Domain
Support Tooling And Documentation
Bucket
Documentation
Inferred role
Support Tooling And Documentation: Documentation
Status
atlas-only

Why This File Exists

Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.

Dependency Surface

Detected Declarations

Annotated Snippet

what:		/sys/kernel/mm/damon/
Date:		Mar 2022
Contact:	SeongJae Park <sj@kernel.org>
Description:	Interface for Data Access MONitoring (DAMON).  Contains files
		for controlling DAMON.  For more details on DAMON itself,
		please refer to Documentation/admin-guide/mm/damon/index.rst.

What:		/sys/kernel/mm/damon/admin/
Date:		Mar 2022
Contact:	SeongJae Park <sj@kernel.org>
Description:	Interface for privileged users of DAMON.  Contains files for
		controlling DAMON that aimed to be used by privileged users.

What:		/sys/kernel/mm/damon/admin/kdamonds/nr_kdamonds
Date:		Mar 2022
Contact:	SeongJae Park <sj@kernel.org>
Description:	Writing a number 'N' to this file creates the number of
		directories for controlling each DAMON worker thread (kdamond)
		named '0' to 'N-1' under the kdamonds/ directory.

What:		/sys/kernel/mm/damon/admin/kdamonds/<K>/state
Date:		Mar 2022
Contact:	SeongJae Park <sj@kernel.org>
Description:	Writing 'on' or 'off' to this file makes the kdamond starts or
		stops, respectively.  Reading the file returns the keywords
		based on the current status.  Writing 'commit' to this file
		makes the kdamond reads the user inputs in the sysfs files
		except 'state' again.  Writing 'commit_schemes_quota_goals' to
		this file makes the kdamond reads the quota goal files again.
		Writing 'update_schemes_stats' to the file updates contents of
		schemes stats files of the kdamond.  Writing
		'update_schemes_tried_regions' to the file updates contents of
		'tried_regions' directory of every scheme directory of this
		kdamond.  Writing 'update_schemes_tried_bytes' to the file
		updates only '.../tried_regions/total_bytes' files of this
		kdamond.  Writing 'clear_schemes_tried_regions' to the file
		removes contents of the 'tried_regions' directory.  Writing
		'update_schemes_effective_quotas' to the file updates
		'.../quotas/effective_bytes' files of this kdamond.

What:		/sys/kernel/mm/damon/admin/kdamonds/<K>/pid
Date:		Mar 2022
Contact:	SeongJae Park <sj@kernel.org>
Description:	Reading this file returns the pid of the kdamond if it is
		running.

What:		/sys/kernel/mm/damon/admin/kdamonds/<K>/refresh_ms
Date:		Jul 2025
Contact:	SeongJae Park <sj@kernel.org>
Description:	Writing a value to this file sets the time interval for
		automatic DAMON status file contents update.  Writing '0'
		disables the update.  Reading this file returns the value.

What:		/sys/kernel/mm/damon/admin/kdamonds/<K>/contexts/nr_contexts
Date:		Mar 2022
Contact:	SeongJae Park <sj@kernel.org>
Description:	Writing a number 'N' to this file creates the number of
		directories for controlling each DAMON context named '0' to
		'N-1' under the contexts/ directory.

What:		/sys/kernel/mm/damon/admin/kdamonds/<K>/contexts/<C>/avail_operations
Date:		Apr 2022
Contact:	SeongJae Park <sj@kernel.org>
Description:	Reading this file returns the available monitoring operations
		sets on the currently running kernel.

What:		/sys/kernel/mm/damon/admin/kdamonds/<K>/contexts/<C>/operations
Date:		Mar 2022
Contact:	SeongJae Park <sj@kernel.org>
Description:	Writing a keyword for a monitoring operations set ('vaddr' for

Annotation

Implementation Notes