sysfs-devices-node

  1What:		/sys/devices/system/node/possible
  2Date:		October 2002
  3Contact:	Linux Memory Management list <linux-mm@kvack.org>
  4Description:
  5		Nodes that could be possibly become online at some point.
  6
  7What:		/sys/devices/system/node/online
  8Date:		October 2002
  9Contact:	Linux Memory Management list <linux-mm@kvack.org>
 10Description:
 11		Nodes that are online.
 12
 13What:		/sys/devices/system/node/has_normal_memory
 14Date:		October 2002
 15Contact:	Linux Memory Management list <linux-mm@kvack.org>
 16Description:
 17		Nodes that have regular memory.
 18
 19What:		/sys/devices/system/node/has_cpu
 20Date:		October 2002
 21Contact:	Linux Memory Management list <linux-mm@kvack.org>
 22Description:
 23		Nodes that have one or more CPUs.
 24
 25What:		/sys/devices/system/node/has_high_memory
 26Date:		October 2002
 27Contact:	Linux Memory Management list <linux-mm@kvack.org>
 28Description:
 29		Nodes that have regular or high memory.
 30		Depends on CONFIG_HIGHMEM.
 31
 32What:		/sys/devices/system/node/nodeX
 33Date:		October 2002
 34Contact:	Linux Memory Management list <linux-mm@kvack.org>
 35Description:
 36		When CONFIG_NUMA is enabled, this is a directory containing
 37		information on node X such as what CPUs are local to the
 38		node. Each file is detailed next.
 39
 40What:		/sys/devices/system/node/nodeX/cpumap
 41Date:		October 2002
 42Contact:	Linux Memory Management list <linux-mm@kvack.org>
 43Description:
 44		The node's cpumap.
 45
 46What:		/sys/devices/system/node/nodeX/cpulist
 47Date:		October 2002
 48Contact:	Linux Memory Management list <linux-mm@kvack.org>
 49Description:
 50		The CPUs associated to the node.
 51
 52What:		/sys/devices/system/node/nodeX/meminfo
 53Date:		October 2002
 54Contact:	Linux Memory Management list <linux-mm@kvack.org>
 55Description:
 56		Provides information about the node's distribution and memory
 57		utilization. Similar to /proc/meminfo, see Documentation/filesystems/proc.rst
 58
 59What:		/sys/devices/system/node/nodeX/numastat
 60Date:		October 2002
 61Contact:	Linux Memory Management list <linux-mm@kvack.org>
 62Description:
 63		The node's hit/miss statistics, in units of pages.
 64		See Documentation/admin-guide/numastat.rst
 65
 66What:		/sys/devices/system/node/nodeX/distance
 67Date:		October 2002
 68Contact:	Linux Memory Management list <linux-mm@kvack.org>
 69Description:
 70		Distance between the node and all the other nodes
 71		in the system.
 72
 73What:		/sys/devices/system/node/nodeX/vmstat
 74Date:		October 2002
 75Contact:	Linux Memory Management list <linux-mm@kvack.org>
 76Description:
 77		The node's zoned virtual memory statistics.
 78		This is a superset of numastat.
 79
 80What:		/sys/devices/system/node/nodeX/compact
 81Date:		February 2010
 82Contact:	Mel Gorman <mel@csn.ul.ie>
 83Description:
 84		When this file is written to, all memory within that node
 85		will be compacted. When it completes, memory will be freed
 86		into blocks which have as many contiguous pages as possible
 87
 88What:		/sys/devices/system/node/nodeX/hugepages/hugepages-<size>/
 89Date:		December 2009
 90Contact:	Lee Schermerhorn <lee.schermerhorn@hp.com>
 91Description:
 92		The node's huge page size control/query attributes.
 93		See Documentation/admin-guide/mm/hugetlbpage.rst
 94
 95What:		/sys/devices/system/node/nodeX/accessY/
 96Date:		December 2018
 97Contact:	Keith Busch <keith.busch@intel.com>
 98Description:
 99		The node's relationship to other nodes for access class "Y".
100
101What:		/sys/devices/system/node/nodeX/accessY/initiators/
102Date:		December 2018
103Contact:	Keith Busch <keith.busch@intel.com>
104Description:
105		The directory containing symlinks to memory initiator
106		nodes that have class "Y" access to this target node's
107		memory. CPUs and other memory initiators in nodes not in
108		the list accessing this node's memory may have different
109		performance.
110
111What:		/sys/devices/system/node/nodeX/accessY/targets/
112Date:		December 2018
113Contact:	Keith Busch <keith.busch@intel.com>
114Description:
115		The directory containing symlinks to memory targets that
116		this initiator node has class "Y" access.
117
118What:		/sys/devices/system/node/nodeX/accessY/initiators/read_bandwidth
119Date:		December 2018
120Contact:	Keith Busch <keith.busch@intel.com>
121Description:
122		This node's read bandwidth in MB/s when accessed from
123		nodes found in this access class's linked initiators.
124
125What:		/sys/devices/system/node/nodeX/accessY/initiators/read_latency
126Date:		December 2018
127Contact:	Keith Busch <keith.busch@intel.com>
128Description:
129		This node's read latency in nanoseconds when accessed
130		from nodes found in this access class's linked initiators.
131
132What:		/sys/devices/system/node/nodeX/accessY/initiators/write_bandwidth
133Date:		December 2018
134Contact:	Keith Busch <keith.busch@intel.com>
135Description:
136		This node's write bandwidth in MB/s when accessed from
137		found in this access class's linked initiators.
138
139What:		/sys/devices/system/node/nodeX/accessY/initiators/write_latency
140Date:		December 2018
141Contact:	Keith Busch <keith.busch@intel.com>
142Description:
143		This node's write latency in nanoseconds when access
144		from nodes found in this class's linked initiators.
145
146What:		/sys/devices/system/node/nodeX/memory_side_cache/indexY/
147Date:		December 2018
148Contact:	Keith Busch <keith.busch@intel.com>
149Description:
150		The directory containing attributes for the memory-side cache
151		level 'Y'.
152
153What:		/sys/devices/system/node/nodeX/memory_side_cache/indexY/indexing
154Date:		December 2018
155Contact:	Keith Busch <keith.busch@intel.com>
156Description:
157		The caches associativity indexing: 0 for direct mapped,
158		non-zero if indexed.
159
160What:		/sys/devices/system/node/nodeX/memory_side_cache/indexY/line_size
161Date:		December 2018
162Contact:	Keith Busch <keith.busch@intel.com>
163Description:
164		The number of bytes accessed from the next cache level on a
165		cache miss.
166
167What:		/sys/devices/system/node/nodeX/memory_side_cache/indexY/size
168Date:		December 2018
169Contact:	Keith Busch <keith.busch@intel.com>
170Description:
171		The size of this memory side cache in bytes.
172
173What:		/sys/devices/system/node/nodeX/memory_side_cache/indexY/write_policy
174Date:		December 2018
175Contact:	Keith Busch <keith.busch@intel.com>
176Description:
177		The cache write policy: 0 for write-back, 1 for write-through,
178		other or unknown.
179
180What:		/sys/devices/system/node/nodeX/memory_side_cache/indexY/address_mode
181Date:		March 2025
182Contact:	Dave Jiang <dave.jiang@intel.com>
183Description:
184		The address mode: 0 for reserved, 1 for extended-linear.
185
186What:		/sys/devices/system/node/nodeX/x86/sgx_total_bytes
187Date:		November 2021
188Contact:	Jarkko Sakkinen <jarkko@kernel.org>
189Description:
190		The total amount of SGX physical memory in bytes.
191
192What:		/sys/devices/system/node/nodeX/memory_failure/total
193Date:		January 2023
194Contact:	Jiaqi Yan <jiaqiyan@google.com>
195Description:
196		The total number of raw poisoned pages (pages containing
197		corrupted data due to memory errors) on a NUMA node.
198
199What:		/sys/devices/system/node/nodeX/memory_failure/ignored
200Date:		January 2023
201Contact:	Jiaqi Yan <jiaqiyan@google.com>
202Description:
203		Of the raw poisoned pages on a NUMA node, how many pages are
204		ignored by memory error recovery attempt, usually because
205		support for this type of pages is unavailable, and kernel
206		gives up the recovery.
207
208What:		/sys/devices/system/node/nodeX/memory_failure/failed
209Date:		January 2023
210Contact:	Jiaqi Yan <jiaqiyan@google.com>
211Description:
212		Of the raw poisoned pages on a NUMA node, how many pages are
213		failed by memory error recovery attempt. This usually means
214		a key recovery operation failed.
215
216What:		/sys/devices/system/node/nodeX/memory_failure/delayed
217Date:		January 2023
218Contact:	Jiaqi Yan <jiaqiyan@google.com>
219Description:
220		Of the raw poisoned pages on a NUMA node, how many pages are
221		delayed by memory error recovery attempt. Delayed poisoned
222		pages usually will be retried by kernel.
223
224What:		/sys/devices/system/node/nodeX/memory_failure/recovered
225Date:		January 2023
226Contact:	Jiaqi Yan <jiaqiyan@google.com>
227Description:
228		Of the raw poisoned pages on a NUMA node, how many pages are
229		recovered by memory error recovery attempt.
230
231What:		/sys/devices/system/node/nodeX/reclaim
232Date:		June 2025
233Contact:	Linux Memory Management list <linux-mm@kvack.org>
234Description:
235		Perform user-triggered proactive reclaim on a NUMA node.
236		This interface is equivalent to the memcg variant.
237
238		See Documentation/admin-guide/cgroup-v2.rst