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Linux kernel mirror (for testing)
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kernel
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linux
1What: /sys/devices/system/memory
2Date: June 2008
3Contact: Badari Pulavarty <pbadari@us.ibm.com>
4Description:
5 The /sys/devices/system/memory contains a snapshot of the
6 internal state of the kernel memory blocks. Files could be
7 added or removed dynamically to represent hot-add/remove
8 operations.
9Users: hotplug memory add/remove tools
10 http://www.ibm.com/developerworks/wikis/display/LinuxP/powerpc-utils
11
12What: /sys/devices/system/memory/memoryX/removable
13Date: June 2008
14Contact: Badari Pulavarty <pbadari@us.ibm.com>
15Description:
16 The file /sys/devices/system/memory/memoryX/removable
17 indicates whether this memory block is removable or not.
18 This is useful for a user-level agent to determine
19 identify removable sections of the memory before attempting
20 potentially expensive hot-remove memory operation
21Users: hotplug memory remove tools
22 http://www.ibm.com/developerworks/wikis/display/LinuxP/powerpc-utils
23
24What: /sys/devices/system/memory/memoryX/phys_device
25Date: September 2008
26Contact: Badari Pulavarty <pbadari@us.ibm.com>
27Description:
28 The file /sys/devices/system/memory/memoryX/phys_device
29 is read-only and is designed to show the name of physical
30 memory device. Implementation is currently incomplete.
31
32What: /sys/devices/system/memory/memoryX/phys_index
33Date: September 2008
34Contact: Badari Pulavarty <pbadari@us.ibm.com>
35Description:
36 The file /sys/devices/system/memory/memoryX/phys_index
37 is read-only and contains the section ID in hexadecimal
38 which is equivalent to decimal X contained in the
39 memory section directory name.
40
41What: /sys/devices/system/memory/memoryX/state
42Date: September 2008
43Contact: Badari Pulavarty <pbadari@us.ibm.com>
44Description:
45 The file /sys/devices/system/memory/memoryX/state
46 is read-write. When read, its contents show the
47 online/offline state of the memory section. When written,
48 root can toggle the the online/offline state of a removable
49 memory section (see removable file description above)
50 using the following commands::
51
52 # echo online > /sys/devices/system/memory/memoryX/state
53 # echo offline > /sys/devices/system/memory/memoryX/state
54
55 For example, if /sys/devices/system/memory/memory22/removable
56 contains a value of 1 and
57 /sys/devices/system/memory/memory22/state contains the
58 string "online" the following command can be executed by
59 by root to offline that section::
60
61 # echo offline > /sys/devices/system/memory/memory22/state
62
63Users: hotplug memory remove tools
64 http://www.ibm.com/developerworks/wikis/display/LinuxP/powerpc-utils
65
66
67What: /sys/devices/system/memory/memoryX/valid_zones
68Date: July 2014
69Contact: Zhang Zhen <zhenzhang.zhang@huawei.com>
70Description:
71 The file /sys/devices/system/memory/memoryX/valid_zones is
72 read-only and is designed to show which zone this memory
73 block can be onlined to.
74
75What: /sys/devices/system/memoryX/nodeY
76Date: October 2009
77Contact: Linux Memory Management list <linux-mm@kvack.org>
78Description:
79 When CONFIG_NUMA is enabled, a symbolic link that
80 points to the corresponding NUMA node directory.
81
82 For example, the following symbolic link is created for
83 memory section 9 on node0:
84
85 /sys/devices/system/memory/memory9/node0 -> ../../node/node0
86
87
88What: /sys/devices/system/node/nodeX/memoryY
89Date: September 2008
90Contact: Gary Hade <garyhade@us.ibm.com>
91Description:
92 When CONFIG_NUMA is enabled
93 /sys/devices/system/node/nodeX/memoryY is a symbolic link that
94 points to the corresponding /sys/devices/system/memory/memoryY
95 memory section directory. For example, the following symbolic
96 link is created for memory section 9 on node0.
97
98 /sys/devices/system/node/node0/memory9 -> ../../memory/memory9