zoukankan      html  css  js  c++  java
  • Linux cat /proc/meminfo 输出分析

    $cat /proc/meminfo
    MemTotal:          2052440 kB //总内存
    MemFree:            50004 kB //空闲内存
    Buffers:             19976 kB //给文件的缓冲大小
    Cached:               436412 kB //高速缓冲存储器(http://baike.baidu.com/view/496990.htm)使用的大小
    SwapCached:        19864 kB //被高速缓冲存储用的交换空间大小
    Active:              1144512 kB //活跃使用中的高速缓冲存储器页面文件大小
    Inactive:            732788 kB //不经常使用的高速缓冲存储器页面文件大小
    Active(anon):          987640 kB //anon:不久
    Inactive(anon):       572512 kB
    Active(file):     156872 kB
    Inactive(file):   160276 kB
    Unevictable:           8 kB
    Mlocked:               8 kB
    HighTotal:       1177160 kB //The total and free amount of memory, in kilobytes, that is not directly mapped into kernel space.
    HighFree:           7396 kB // The HighTotal value can vary based on the type of kernel used.
    LowTotal:         875280 kB // The total and free amount of memory, in kilobytes, that is directly mapped into kernel space.  used.
    LowFree:           42608 kB //The LowTotal value can vary based on the type of kernel
    SwapTotal:        489940 kB //交换空间总大小
    SwapFree:         450328 kB //空闲交换空间
    Dirty:               104 kB //等待被写回到磁盘的大小
    Writeback:             0 kB //正在被写回的大小
    AnonPages:       1408256 kB //未映射的页的大小
    Mapped:           131964 kB //设备和文件映射的大小
    Slab:              37368 kB //内核数据结构缓存的大小,可减少申请和释放内存带来的消耗
    SReclaimable:      14164 kB //可收回slab的大小
    SUnreclaim:        23204 kB //不可收回的slab的大小23204+14164=37368
    PageTables:        13308 kB //管理内存分页的索引表的大小
    NFS_Unstable:          0 kB //不稳定页表的大小
    Bounce:                0 kB //bounce:退回
    WritebackTmp:          0 kB //
    CommitLimit:     1516160 kB
    Committed_AS:    2511900 kB
    VmallocTotal:     122880 kB //虚拟内存大小
    VmallocUsed:       28688 kB //已经被使用的虚拟内存大小
    VmallocChunk:      92204 kB
    HugePages_Total:       0 //大页面的分配
    HugePages_Free:        0
    HugePages_Rsvd:        0
    HugePages_Surp:        0
    Hugepagesize:       2048 kB
    DirectMap4k:       10232 kB
    DirectMap2M:      899072 kB

    ========================================================================================
    相应选项中文意思想各位高手已经知道,如何翻译有什么错误,请务必指出:
        MemTotal: 所有可用RAM大小 (即物理内存减去一些预留位和内核的二进制代码大小)
         MemFree: LowFree与HighFree的总和,被系统留着未使用的内存
         Buffers: 用来给文件做缓冲大小
          Cached: 被高速缓冲存储器(cache memory)用的内存的大小(等于 diskcache minus SwapCache ).
      SwapCached:被高速缓冲存储器(cache memory)用的交换空间的大小
                 已经被交换出来的内存,但仍然被存放在swapfile中。用来在需要的时候很快的被替换而不需要再次打开I/O端口。
          Active: 在活跃使用中的缓冲或高速缓冲存储器页面文件的大小,除非非常必要否则不会被移作他用.
        Inactive: 在不经常使用中的缓冲或高速缓冲存储器页面文件的大小,可能被用于其他途径.
       HighTotal:
        HighFree: 该区域不是直接映射到内核空间。内核必须使用不同的手法使用该段内存。
        LowTotal:
         LowFree: 低位可以达到高位内存一样的作用,而且它还能够被内核用来记录一些自己的数据结构。Among many
                  other things, it is where everything from the Slab is
                  allocated.  Bad things happen when you're out of lowmem.
             
       SwapTotal: 交换空间的总大小
        SwapFree: 未被使用交换空间的大小
        Dirty: 等待被写回到磁盘的内存大小。
         
       Writeback: 正在被写回到磁盘的内存大小。
      
       AnonPages:未映射页的内存大小
      
       Mapped: 设备和文件等映射的大小。
      
       Slab: 内核数据结构缓存的大小,可以减少申请和释放内存带来的消耗。
       SReclaimable:可收回Slab的大小
      
       SUnreclaim:不可收回Slab的大小(SUnreclaim+SReclaimable=Slab)
      
       PageTables:管理内存分页页面的索引表的大小。
      
       NFS_Unstable:不稳定页表的大小
      
       Bounce:
     CommitLimit: Based on the overcommit ratio ('vm.overcommit_ratio'),
                  this is the total amount of  memory currently available to
                  be allocated on the system. This limit is only adhered to
                  if strict overcommit accounting is enabled (mode 2 in
                  'vm.overcommit_memory').
                  The CommitLimit is calculated with the following formula:
                  CommitLimit = ('vm.overcommit_ratio' * Physical RAM) + Swap
                  For example, on a system with 1G of physical RAM and 7G
                  of swap with a `vm.overcommit_ratio` of 30 it would
                  yield a CommitLimit of 7.3G.
                  For more details, see the memory overcommit documentation
                  in vm/overcommit-accounting.
                 
    Committed_AS: The amount of memory presently allocated on the system.
                  The committed memory is a sum of all of the memory which
                  has been allocated by processes, even if it has not been
                  "used" by them as of yet. A process which malloc()'s 1G
                  of memory, but only touches 300M of it will only show up
                  as using 300M of memory even if it has the address space
                  allocated for the entire 1G. This 1G is memory which has
                  been "committed" to by the VM and can be used at any time
                  by the allocating application. With strict overcommit
                  enabled on the system (mode 2 in 'vm.overcommit_memory'),
                  allocations which would exceed the CommitLimit (detailed
                  above) will not be permitted. This is useful if one needs
                  to guarantee that processes will not fail due to lack of
                  memory once that memory has been successfully allocated.
    VmallocTotal: 可以vmalloc虚拟内存大小
    VmallocUsed: 已经被使用的虚拟内存大小。
    VmallocChunk: largest contigious block of vmalloc area which is free

  • 相关阅读:
    一文读懂快速排序
    15道APP测试面试题分享,助攻你的面试
    APP测试之使用ADB可能遇到的错误及解决办法
    APP测试之Monkey压力测试(二)
    APP测试之Monkey压力测试(一)
    APP日志文件抓取及分析
    Linux环境安装python3
    visualvm 插件 visual gc 使用介绍
    设计模式之状态
    【深入理解JVM】:Java内存模型JMM
  • 原文地址:https://www.cnblogs.com/langzou/p/7444316.html
Copyright © 2011-2022 走看看