zoukankan      html  css  js  c++  java
  • linux 磁盘

    1.查看内存

    [root@greymouster ~]# free -m    #以M查内容
                 total       used       free     shared    buffers     cached
    Mem:          1006        163        843          0      22         72
    -/+ buffers/cache:         68        938
    Swap:         2047          0       2047
    [root@greymouster ~]# free 
                 total       used       free     shared    buffers     cached
    Mem:       1030492     166972     863520        248      23160      73992
    -/+ buffers/cache:      69820     960672
    Swap:      2097148          0    2097148
    [root@greymouster ~]# 

    提示:1)linux系统的特性是将系统不用的物理内存缓存起来,因此843 不是系统的真实内存

            2) 系统真正系统内存是938M

            3)buffers 为写入缓冲区,sync 将buffer缓冲区数据写入磁盘,cache 为读出缓存

    查看磁盘:

    [root@greymouster ~]# fdisk -l
    
    Disk /dev/sda: 21.5 GB, 21474836480 bytes
    255 heads, 63 sectors/track, 2610 cylinders
    Units = cylinders of 16065 * 512 = 8225280 bytes
    Sector size (logical/physical): 512 bytes / 512 bytes
    I/O size (minimum/optimal): 512 bytes / 512 bytes
    Disk identifier: 0x000e5001
    
       Device Boot      Start         End      Blocks   Id  System
    /dev/sda1   *           1          26      204800   83  Linux
    Partition 1 does not end on cylinder boundary.
    /dev/sda2              26         287     2097152   82  Linux swap / Solaris
    Partition 2 does not end on cylinder boundary.
    /dev/sda3             287        2611    18668544   83  Linux

    [root@greymouster ~]# echo $((2610*255*512*63))

      21467980800

    
    

        磁盘大小=磁道数*磁头数*512字节*扇区数

    
    

               =  2610 *  255  *  512   *63

     
  • 相关阅读:
    时间戳 时间 相互转换
    CS Academy Remove Update
    一周水题集锦 2017 9.4
    计蒜客 16877 卡牌游戏
    计蒜客 16876 韩梅梅的抽象画
    九度OJ 题目1534:数组中第K小的数字
    CS Academy Switch the Lights
    CF AIM Tech Round 4 C. Sorting by Subsequences
    CF Round 430 C. Ilya And The Tree
    CS Academy Round 44 Check DFS
  • 原文地址:https://www.cnblogs.com/chenchenphp/p/6261958.html
Copyright © 2011-2022 走看看