Zabbix Documentation 4.4

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manual:appendix:items:vm.memory.size_params

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manual:appendix:items:vm.memory.size_params [2019/02/25 08:41]
martins-v 'cached' is also counted into available for linux <3.14
manual:appendix:items:vm.memory.size_params [2020/03/09 09:30] (current)
martins-v warning level for the note
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 === Overview === === Overview ===
  
-This section provides ​more details ​and platform-specific information on the parameters of the ''​vm.memory.size[<​mode>​]'' ​[[:​manual/​config/​items/​itemtypes/​zabbix_agent|agent item]].+This section provides ​some parameter ​details ​for the [[:​manual/​config/​items/​itemtypes/​zabbix_agent|vm.memory.size[<​mode>​]]] ​agent item.
  
 === Parameters === === Parameters ===
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   * **free** - memory that is readily available to any entity requesting memory   * **free** - memory that is readily available to any entity requesting memory
   * **inactive** - memory that is marked as not used   * **inactive** - memory that is marked as not used
-  * **pavailable** - inactive + cached + free memory as percentage of '​total'​+  * **pavailable** - '​available' ​memory as percentage of '​total' ​(calculated as ''​available''/''​total''​*100)
   * **pinned** - same as '​wired'​   * **pinned** - same as '​wired'​
-  * **pused** - active + wired memory as percentage of '​total'​+  * **pused** - '​used' ​memory as percentage of '​total' ​(calculated as ''​used''/''​total''​*100)
   * **shared** - memory that may be simultaneously accessed by multiple processes   * **shared** - memory that may be simultaneously accessed by multiple processes
   * **slab** - total amount of memory used by the kernel to cache data structures for its own use   * **slab** - total amount of memory used by the kernel to cache data structures for its own use
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   * **wired** - memory that is marked to always stay in RAM. It is never moved to disk.   * **wired** - memory that is marked to always stay in RAM. It is never moved to disk.
  
-<​note ​important>Some of these parameters are platform-specific and might not be available on your platform. ​Please refer to [[:​manual/​appendix/​items/​supported_by_platform|this page]] for details.</​note>​+<​note ​warning>Some of these parameters are platform-specific and might not be available on your platform. ​See [[:​manual/​appendix/​items/​supported_by_platform|Items supported by platform]] for details.</​note>​
  
 Platform-specific calculation of **available** and **used**: Platform-specific calculation of **available** and **used**:
  
-^ Platform ^ **"​available"​** ^ **"​used"​** ^+^ Platform ^ **%%"​available"​%%** ^ **%%"​used"​%%** ^
 |//​AIX// ​        |free + cached |real memory in use| |//​AIX// ​        |free + cached |real memory in use|
 |//​FreeBSD// ​    ​|inactive + cached + free |active + wired + cached ​ | |//​FreeBSD// ​    ​|inactive + cached + free |active + wired + cached ​ |
 |//HP UX//       ​|free |total - free  | |//HP UX//       ​|free |total - free  |
 |//​Linux<​3.14//​ |free + buffers + cached |total - free  | |//​Linux<​3.14//​ |free + buffers + cached |total - free  |
-|//Linux 3.14+// |/​proc/​meminfo,​ "Cached":+"​MemAvailable:"​ |total - free  |+|//Linux 3.14+//\\ (also backported to 3.10 on RHEL 7) |/​proc/​meminfo, ​see %%"MemAvailable"%% in Linux kernel [[https://​www.kernel.org/​doc/​Documentation/​filesystems/​proc.txt|documentation]] for details.\\ Note that free buffers + cached is no longer equal to '​available'​ due to not all the page cache can be freed and low watermark being used in calculation.  ​|total - free  |
 |//​NetBSD// ​     |inactive + execpages + file + free |total - free  | |//​NetBSD// ​     |inactive + execpages + file + free |total - free  |
 |//​OpenBSD// ​    ​|inactive + free + cached |active + wired  | |//​OpenBSD// ​    ​|inactive + free + cached |active + wired  |
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 <note important>​The sum of //​vm.memory.size[used]//​ and //​vm.memory.size[available]//​ does not necessarily equal total. For instance, on FreeBSD:\\ * Active, inactive, wired, cached memories are considered used, because they store some useful information.\\ * At the same time inactive, cached, free memories are considered available, because these kinds of memories can be given instantly to processes that request more memory.\\ \\ So inactive memory is both used and available simultaneously. Because of this, the //​vm.memory.size[used]//​ item is designed for informational purposes only, while //​vm.memory.size[available]//​ is designed to be used in triggers.</​note>​ <note important>​The sum of //​vm.memory.size[used]//​ and //​vm.memory.size[available]//​ does not necessarily equal total. For instance, on FreeBSD:\\ * Active, inactive, wired, cached memories are considered used, because they store some useful information.\\ * At the same time inactive, cached, free memories are considered available, because these kinds of memories can be given instantly to processes that request more memory.\\ \\ So inactive memory is both used and available simultaneously. Because of this, the //​vm.memory.size[used]//​ item is designed for informational purposes only, while //​vm.memory.size[available]//​ is designed to be used in triggers.</​note>​
- 
-See the [[#​see_also|"​See also"​]] section at the bottom of this page to find more detailed information about memory calculation in different OS. 
- 
-== Platform-specific notes == 
- 
-  * on Linux **shared** works only on kernel 2.4 
  
 ==== See also  ==== ==== See also  ====
-  - [[http://​blog.zabbix.com/​when-alexei-isnt-looking#​vm.memory.size|Detailed information ​about memory calculation in different OS]]+  - [[http://​blog.zabbix.com/​when-alexei-isnt-looking#​vm.memory.size|Additional details ​about memory calculation in different OS]]
    
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