Zabbix Documentation 3.4

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manual:appendix:items:vm.memory.size_params

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manual:appendix:items:vm.memory.size_params [2015/03/09 14:40]
wiper [Platform-specific notes] Removed AIX from comment that on AIX and Solaris available and free memory returns the same values
manual:appendix:items:vm.memory.size_params [2019/02/25 08:43] (current)
martins-v 'cached' is also counted into available for linux <3.14
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 ==== 2 vm.memory.size parameters ==== ==== 2 vm.memory.size parameters ====
  
-  ​* **total** - total physical ​memory available. +=== Overview === 
-  * **free** - memory that is readily available to any entity requesting memory. + 
-  * **active** - memory ​currently in use or very recently used, and so it is in RAM. +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]]. 
-  * **inactive** - memory ​that is marked ​as not used.+ 
 +=== Parameters === 
 + 
 +The following parameters are possible for this item: 
 + 
 +  ​* **active** - memory ​currently in use or very recently used, and so it is in RAM 
 +  * **anon** - memory not associated with a file (cannot be re-read from it) 
 +  * **available** - available memory, calculated differently depending on the platform (see the table below) 
 +  * **buffers** - cache for things like file system metadata 
 +  * **cached** - cache for various things 
 +  * **exec** - executable code, typically from a (program) file 
 +  * **file** - cache for contents of recently accessed files 
 +  * **free** - memory that is readily available to any entity requesting memory 
 +  * **inactive** - memory ​that is marked as not used 
 +  * **pavailable** - inactive ​+ cached + free memory as percentage of '​total'​ 
 +  * **pinned** - same as '​wired'​ 
 +  * **pused** - active + wired memory as percentage of '​total'​ 
 +  * **shared** - memory that may be simultaneously accessed by multiple processes 
 +  * **total** - total physical memory available 
 +  * **used** - used memory, calculated differently depending on the platform (see the table below)
   * **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.
-  * **pinned** - same as '​wired'​. 
-  * **anon** - memory not associated with a file (cannot be re-read from it). 
-  * **exec** - executable code, typically from a (program) file. 
-  * **file** - cache for contents of recently accessed files. 
-  * **buffers** - cache for things like file system metadata. 
-  * **cached** - cache for various things. 
-  * **shared** - memory that may be simultaneously accessed by multiple processes. 
-  * **used** - active + wired memory. 
-  * **pused** - active + wired memory in relation to total. 
-  * **available** - inactive + cached + free memory. 
-  * **pavailable** - inactive + cached + free memory in relation to '​total'​. 
  
-<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, item //​vm.memory.size[used]//​ is designed for informational purposes only, while item //​vm.memory.size[available]//​ is designed to be used in triggers.\\ </​note>​+Platform-specific calculation ​of **available** and **used**:
  
-<​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.</​note>​+^ Platform ^ **"​available"​** ^ **"​used"​** ^ 
 +|//​AIX// ​        |free + cached |real memory in use| 
 +|//​FreeBSD// ​    ​|inactive + cached + free |active + wired + cached ​ | 
 +|//HP UX//       ​|free |total - free  | 
 +|//Linux<3.14// |free + buffers + cached |total - free  | 
 +|//Linux 3.14+// |/​proc/​meminfo,​ "​Cached":​+"​MemAvailable:"​ |total - free  | 
 +|//​NetBSD// ​     |inactive + execpages + file + free |total - free  | 
 +|//​OpenBSD// ​    ​|inactive + free + cached |active + wired  | 
 +|//​OSX// ​        ​|inactive + free |active + wired  | 
 +|//​Solaris// ​    ​|free |total - free  | 
 +|//​Win32// ​      ​|free |total - free  | 
 + 
 +<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 == == Platform-specific notes ==
  
-  * on Solaris **available** and **free** are the same 
   * on Linux **shared** works only on kernel 2.4   * 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|Detailed information about memory calculation in different OS]]
-