Linux Command pmap 测试进程内存映射工具
1. 简介
pmap命令用于报告进程的内存映射关系，是Linux调试及运维一个很好的工具。
2. 语法
pmap [ -x | -d ] [ -q ] pids...
pmap -V
3. 参数
-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
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
4. 实例
4.1 查看进程1设备格式
[root@C44 ~]# pmap -d 1
1: init [5]
Address Kbytes Mode Offset Device Mapping
00934000 88 r-x-- 0000000000000000 008:00005 ld-2.3.4.so
0094a000 4 r---- 0000000000015000 008:00005 ld-2.3.4.so
0094b000 4 rw--- 0000000000016000 008:00005 ld-2.3.4.so
0094e000 1188 r-x-- 0000000000000000 008:00005 libc-2.3.4.so
00a77000 8 r---- 0000000000129000 008:00005 libc-2.3.4.so
00a79000 8 rw--- 000000000012b000 008:00005 libc-2.3.4.so
00a7b000 8 rw--- 0000000000a7b000 000:00000 [ anon ]
00a85000 52 r-x-- 0000000000000000 008:00005 libsepol.so.1
00a92000 4 rw--- 000000000000c000 008:00005 libsepol.so.1
00a93000 32 rw--- 0000000000a93000 000:00000 [ anon ]
00d9d000 52 r-x-- 0000000000000000 008:00005 libselinux.so.1
00daa000 4 rw--- 000000000000d000 008:00005 libselinux.so.1
08048000 28 r-x-- 0000000000000000 008:00005 init
0804f000 4 rw--- 0000000000007000 008:00005 init
084e1000 132 rw--- 00000000084e1000 000:00000 [ anon ]
b7f5d000 8 rw--- 00000000b7f5d000 000:00000 [ anon ]
bffee000 72 rw--- 00000000bffee000 000:00000 [ stack ]
ffffe000 4 ----- 0000000000000000 000:00000 [ anon ]
mapped: 1700K writeable/private: 276K shared: 0K
最后一行的值
- 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
4.2 查看进程1设备格式不显示头尾行
[root@C44 ~]# pmap -d -q 1
1: init [5]
00934000 88 r-x-- 0000000000000000 008:00005 ld-2.3.4.so
0094a000 4 r---- 0000000000015000 008:00005 ld-2.3.4.so
0094b000 4 rw--- 0000000000016000 008:00005 ld-2.3.4.so
0094e000 1188 r-x-- 0000000000000000 008:00005 libc-2.3.4.so
00a77000 8 r---- 0000000000129000 008:00005 libc-2.3.4.so
00a79000 8 rw--- 000000000012b000 008:00005 libc-2.3.4.so
00a7b000 8 rw--- 0000000000a7b000 000:00000 [ anon ]
00a85000 52 r-x-- 0000000000000000 008:00005 libsepol.so.1
00a92000 4 rw--- 000000000000c000 008:00005 libsepol.so.1
00a93000 32 rw--- 0000000000a93000 000:00000 [ anon ]
00d9d000 52 r-x-- 0000000000000000 008:00005 libselinux.so.1
00daa000 4 rw--- 000000000000d000 008:00005 libselinux.so.1
08048000 28 r-x-- 0000000000000000 008:00005 init
0804f000 4 rw--- 0000000000007000 008:00005 init
084e1000 132 rw--- 00000000084e1000 000:00000 [ anon ]
b7f5d000 8 rw--- 00000000b7f5d000 000:00000 [ anon ]
bffee000 72 rw--- 00000000bffee000 000:00000 [ stack ]
ffffe000 4 ----- 0000000000000000 000:00000 [ anon ]
4.3 查看进程1扩展格式
[root@C44 ~]# pmap -x 1
1: init [5]
Address Kbytes RSS Anon Locked Mode Mapping
00934000 88 - - - r-x-- ld-2.3.4.so
0094a000 4 - - - r---- ld-2.3.4.so
0094b000 4 - - - rw--- ld-2.3.4.so
0094e000 1188 - - - r-x-- libc-2.3.4.so
00a77000 8 - - - r---- libc-2.3.4.so
00a79000 8 - - - rw--- libc-2.3.4.so
00a7b000 8 - - - rw--- [ anon ]
00a85000 52 - - - r-x-- libsepol.so.1
00a92000 4 - - - rw--- libsepol.so.1
00a93000 32 - - - rw--- [ anon ]
00d9d000 52 - - - r-x-- libselinux.so.1
00daa000 4 - - - rw--- libselinux.so.1
08048000 28 - - - r-x-- init
0804f000 4 - - - rw--- init
084e1000 132 - - - rw--- [ anon ]
b7f5d000 8 - - - rw--- [ anon ]
bffee000 72 - - - rw--- [ stack ]
ffffe000 4 - - - ----- [ anon ]
-------- ------- ------- ------- -------
total kB 1700 - - -
4.4 循环显示进程3066设备格式最后1行
间隔2秒
[root@C44 ~]# while true; do pmap -d 3066 | tail -1; sleep 2; done
mapped: 5412K writeable/private: 2028K shared: 0K
mapped: 5412K writeable/private: 2028K shared: 0K
mapped: 5412K writeable/private: 2028K shared: 0K
mapped: 5412K writeable/private: 2028K shared: 0K
mapped: 5412K writeable/private: 2028K shared: 0K
mapped: 5412K writeable/private: 2028K shared: 0K
mapped: 5412K writeable/private: 2028K shared: 0K
mapped: 5412K writeable/private: 2028K shared: 0K
mapped: 5412K writeable/private: 2028K shared: 0K
mapped: 5412K writeable/private: 2028K shared: 0K
mapped: 5412K writeable/private: 2028K shared: 0K
mapped: 5412K writeable/private: 2028K shared: 0K
mapped: 5412K writeable/private: 2028K shared: 0K
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