Linux之pmap

一、pmap简介
        （1）名称：
        pmap - report memory map of a process(查看进程的内存映像信息)
        （2）用法
        pmap [ -x | -d ] [ -q ] pids...
        pmap -V
        （3）选项含义
        -x   extended       Show the extended format. 显示扩展格式
        -d   device         Show the device format.   显示设备格式
        -q   quiet          Do not display some header/footer lines. 不显示头尾行
        -V   show version   Displays version of program. 显示版本
        （4）扩展格式和设备格式域
        Address:  start address of map  映像起始地址
        Kbytes:  size of map in kilobytes  映像大小
        RSS:  resident set size in kilobytes  驻留集大小
        Dirty:  dirty pages (both shared and private) in kilobytes  脏页大小
        Mode:  permissions on map 映像权限: r=read, w=write, x=execute, s=shared, p=private (copy on write)  
        Mapping:  file backing the map , or '[ anon ]' for allocated memory, or '[ stack ]' for the program stack.  映像支持文件,[anon]为已分配内存 [stack]为程序堆栈
        Offset:  offset into the file  文件偏移
        Device:  device name (major:minor)  设备名

二、应用举例
        [xxx@xxx ~]# pmap -d 21147               
        21147:   ./ogassistservice
        Address            Kbytes Mode  Offset           Device    Mapping
        0000000000400000     360 r-x-- 0000000000000000 003:00002 ogassistservice
        000000000065a000       4 rw--- 000000000005a000 003:00002 ogassistservice
        000000000065b000     128 rw--- 000000000065b000 000:00000   [ anon ]
        0000000011232000  523804 rw--- 0000000011232000 000:00000   [ anon ]
        0000003304000000      12 r-x-- 0000000000000000 003:00002 libuuid.so.1.2
        0000003304003000    2048 ----- 0000000000003000 003:00002 libuuid.so.1.2
        0000003304203000       4 rw--- 0000000000003000 003:00002 libuuid.so.1.2
        000000376d000000     920 r-x-- 0000000000000000 003:00002 libstdc++.so.6.0.8
        000000376d0e6000    2044 ----- 00000000000e6000 003:00002 libstdc++.so.6.0.8
        000000376d2e5000      24 r---- 00000000000e5000 003:00002 libstdc++.so.6.0.8
        000000376d2eb000      12 rw--- 00000000000eb000 003:00002 libstdc++.so.6.0.8
        000000376d2ee000      72 rw--- 000000376d2ee000 000:00000   [ anon ]
        0000003bc5800000     112 r-x-- 0000000000000000 003:00002 ld-2.5.so
        0000003bc5a1b000       4 r---- 000000000001b000 003:00002 ld-2.5.so
        0000003bc5a1c000       4 rw--- 000000000001c000 003:00002 ld-2.5.so
        0000003bc5c00000    1336 r-x-- 0000000000000000 003:00002 libc-2.5.so
        0000003bc5d4e000    2048 ----- 000000000014e000 003:00002 libc-2.5.so
        0000003bc5f4e000      16 r---- 000000000014e000 003:00002 libc-2.5.so    
        0000003bc5f52000       4 rw--- 0000000000152000 003:00002 libc-2.5.so
        0000003bc5f53000      20 rw--- 0000003bc5f53000 000:00000   [ anon ]
        0000003bc6000000       8 r-x-- 0000000000000000 003:00002 libdl-2.5.so
        0000003bc6002000    2048 ----- 0000000000002000 003:00002 libdl-2.5.so
        0000003bc6202000       4 r---- 0000000000002000 003:00002 libdl-2.5.so
        0000003bc6203000       4 rw--- 0000000000003000 003:00002 libdl-2.5.so
        0000003bc6400000     520 r-x-- 0000000000000000 003:00002 libm-2.5.so
        0000003bc6482000    2044 ----- 0000000000082000 003:00002 libm-2.5.so
        0000003bc6681000       4 r---- 0000000000081000 003:00002 libm-2.5.so
        0000003bc6682000       4 rw--- 0000000000082000 003:00002 libm-2.5.so
        0000003bc6800000      88 r-x-- 0000000000000000 003:00002 libpthread-2.5.so
        0000003bc6816000    2044 ----- 0000000000016000 003:00002 libpthread-2.5.so
        0000003bc6a15000       4 r---- 0000000000015000 003:00002 libpthread-2.5.so
        0000003bc6a16000       4 rw--- 0000000000016000 003:00002 libpthread-2.5.so    
        0000003bc6a17000      16 rw--- 0000003bc6a17000 000:00000   [ anon ]
        0000003bc6c00000      80 r-x-- 0000000000000000 003:00002 libz.so.1.2.3
        0000003bc6c14000    2044 ----- 0000000000014000 003:00002 libz.so.1.2.3
        0000003bc6e13000       4 rw--- 0000000000013000 003:00002 libz.so.1.2.3
        0000003bc7800000      28 r-x-- 0000000000000000 003:00002 librt-2.5.so
        0000003bc7807000    2048 ----- 0000000000007000 003:00002 librt-2.5.so
        0000003bc7a07000       4 r---- 0000000000007000 003:00002 librt-2.5.so
        0000003bc7a08000       4 rw--- 0000000000008000 003:00002 librt-2.5.so
        0000003bc7c00000      52 r-x-- 0000000000000000 003:00002 libgcc_s-4.1.2-20080825.so.1
        0000003bc7c0d000    2048 ----- 000000000000d000 003:00002 libgcc_s-4.1.2-20080825.so.1
        0000003bc7e0d000       4 rw--- 000000000000d000 003:00002 libgcc_s-4.1.2-20080825.so.1
        00002b7b46c54000      20 rw--- 00002b7b46c54000 000:00000   [ anon ]
        00002b7b46c5a000       4 rw--- 00002b7b46c5a000 000:00000   [ anon ]
        00002b7b46c66000     260 r-x-- 0000000000000000 003:00004 libevent.so
        00002b7b46ca7000    2048 ----- 0000000000041000 003:00004 libevent.so
        00002b7b46ea7000       8 rw--- 0000000000041000 003:00004 libevent.so
        00002b7b46ea9000       4 rw--- 00002b7b46ea9000 000:00000   [ anon ]
        00002b7b46eaa000     968 r-x-- 0000000000000000 003:00004 libprotobuf.so
        00002b7b46f9c000    2044 ----- 00000000000f2000 003:00004 libprotobuf.so
        00002b7b4719b000      24 rw--- 00000000000f1000 003:00004 libprotobuf.so
        00002b7b471a1000     504 r-x-- 0000000000000000 003:00004 liblog4cplus.so
        00002b7b4721f000    2048 ----- 000000000007e000 003:00004 liblog4cplus.so
        00002b7b4741f000      24 rw--- 000000000007e000 003:00004 liblog4cplus.so
        00002b7b47425000      48 r-x-- 0000000000000000 003:00004 librabbitmq.so
        00002b7b47431000    2044 ----- 000000000000c000 003:00004 librabbitmq.so
        00002b7b47630000       4 rw--- 000000000000b000 003:00004 librabbitmq.so
        00002b7b47631000    1048 rw--- 00002b7b47631000 000:00000   [ anon ]
        00007fffd6054000      84 rw--- 00007ffffffe9000 000:00000   [ stack ]
        00007fffd61ac000      16 r-x-- 00007fffd61ac000 000:00000   [ anon ]
        ffffffffff600000    8192 ----- 0000000000000000 000:00000   [ anon ]
        mapped: 565476K    writeable/private: 525312K    shared: 0K
        上面这一堆中，最后一行的值必须知道：
        mapped 表示该进程映射的虚拟地址空间大小，也就是该进程预先分配的虚拟内存大小，即ps出的vsz
        writeable/private  表示进程所占用的私有地址空间大小，也就是该进程实际使用的内存大小      
        shared 表示进程和其他进程共享的内存大小

三、其它命令
        除了pmap外，其实还有别的手段可以用于静态查看某个进程的内存使用情况：
        （1）ps
        ps -aux|grep process_name
        （2）cat /proc/process_id/status
        Name:   xxx
        State:  S (sleeping)
        SleepAVG:       98%
        Tgid:   21147
        Pid:    21147
        PPid:   18228
        TracerPid:      0
        Uid:    0       0       0       0
        Gid:    0       0       0       0
        FDSize: 131072
        Groups: 0 1 2 6 10 
        VmPeak:   557288 kB
        VmSize:   557288 kB
        VmLck:         0 kB
        VmHWM:    527480 kB
        VmRSS:    527480 kB
        VmData:   525132 kB
        VmStk:        88 kB
        VmExe:       360 kB
        VmLib:      4936 kB
        VmPTE:      1140 kB
        StaBrk: 11232000 kB
        Brk:    311b9000 kB
        StaStk: 7fffd60678c0 kB
        Threads:        1
        SigQ:   0/16383
        SigPnd: 0000000000000000
        ShdPnd: 0000000000000000
        SigBlk: 0000000000000000
        SigIgn: 0000000000001000
        SigCgt: 0000000180000000
        CapInh: 0000000000000000
        CapPrm: 00000000fffffeff
        CapEff: 00000000fffffeff
        Cpus_allowed:   00000000,00000000,00000000,00000000,00000000,00000000,7fffffff,ffffffff
        Mems_allowed:   00000000,00000001
        上面这一堆中有两个重要参数必须知道：
        VmSize：任务虚拟地址空间大小
        VmRSS：应用程序正在使用的物理内存大小