2.6.16后的内核, 对于查看进程内存使用分布, 更方便了. 在/proc/{pid} 路径下有一个smaps文件, 记录了进程内存使用情况, 在老的内核系统上, 这个文件是maps或memap , 而且老的内核下maps或memap文件记录的数据真不是人读的.
现在有了高内核, 当然可以用起来了.
smaps文件内容格式是:
7f4913d8f000-7f4913ddd000 r-xp 00000000 fd:00 791940 /usr/local/boost149/lib/libboost_python.so.1.49.0
Size: 312 kB
Rss: 20 kB
Pss: 2 kB
Shared_Clean: 20 kB
Shared_Dirty: 0 kB
Private_Clean: 0 kB
Private_Dirty: 0 kB
Referenced: 20 kB
Anonymous: 0 kB
AnonHugePages: 0 kB
Swap: 0 kB
KernelPageSize: 4 kB
MMUPageSize: 4 kB
size： 是进程使用内存空间，并不一定实际分配了物理内存；
Rss： “Resident Set Size”，实际驻留”在内存中”的内存数. 不包括已经交换出去的页面。RSS还包括了与其它进程共享的内存区域，通常用于共享库；
Pss： Private Rss， Rss中私有的内存页面；
Shared_Clean： Rss中和其他进程共享的未改写页面；
Shared_Dirty： Rss和其他进程共享的已改写页面；
Private_Clean： Rss中改写的私有页面页面；
Private_Dirty： Rss中已改写的私有页面页面；
(其中Dirty页面如果没有交换机制的情况下，应该是不能回收的)
网上有仁兄使用的过滤分析此文件内容的perl脚本, 借来用:
#!/usr/bin/perl
# Copyright Ben Maurer
# you can distribute this under the MIT/X11 License
use Linux::Smaps;
my $pid=shift @ARGV;
unless ($pid) {
print "./smem.pl /n";
exit 1;
}
my $map=Linux::Smaps->new($pid);
my @VMAs = $map->vmas;
format STDOUT =
VMSIZE: @######## kb
$map->size
RSS: @######## kb total
$map->rss
@######## kb shared
$map->shared_clean + $map->shared_dirty
@######## kb private clean
$map->private_clean
@######## kb private dirty
$map->private_dirty
.
write;
printPrivateMappings ();
printSharedMappings ();
sub sharedMappings () {
return grep { ($_->shared_clean + $_->shared_dirty) > 0 } @VMAs;
}
sub privateMappings () {
return grep { ($_->private_clean + $_->private_dirty) > 0 } @VMAs;
}
sub printPrivateMappings ()
{
$TYPE = "PRIVATE MAPPINGS";
$^ = 'SECTION_HEADER';
$~ = 'SECTION_ITEM';
$- = 0;
$= = 100000000;
foreach $vma (sort {-($a->private_dirty <=> $b->private_dirty)}
privateMappings ()) {
$size = $vma->size;
$dirty = $vma->private_dirty;
$clean = $vma->private_clean;
$file = $vma->file_name;
write;
}
}
sub printSharedMappings ()
{
$TYPE = "SHARED MAPPINGS";
$^ = 'SECTION_HEADER';
$~ = 'SECTION_ITEM';
$- = 0;
$= = 100000000;
foreach $vma (sort {-(($a->shared_clean + $a->shared_dirty)
<=>
($b->shared_clean + $b->shared_dirty))}
sharedMappings ()) {
$size = $vma->size;
$dirty = $vma->shared_dirty;
$clean = $vma->shared_clean;
$file = $vma->file_name;
write;
}
}
format SECTION_HEADER =
@<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
$TYPE
@>>>>>>>>>> @>>>>>>>>>> @>>>>>>>>> @<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
"vmsize" "rss clean" "rss dirty" "file"
.
format SECTION_ITEM =
@####### kb @####### kb @####### kb @<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
$size $clean $dirty $file
.
</code>
</pre>
使用之前需要先安装Linux::Smaps模块:
perl -MCPAN -e 'install Linux::Smaps'
使用之:
[root@211 tmp]# perl p.pl 6490
VMSIZE: 835412 kb
RSS: 274928 kb total
2880 kb shared
8112 kb private clean
263936 kb private dirty
PRIVATE MAPPINGS
vmsize rss clean rss dirty file
406380 kb 7432 kb 258816 kb [heap]
6272 kb 0 kb 3612 kb
4048 kb 28 kb 364 kb /terminus/crown/bin/ares
520 kb 56 kb 216 kb
604 kb 112 kb 176 kb
260 kb 20 kb 160 kb
240 kb 32 kb 128 kb /usr/lib64/libpython2.6.so.1.0
260 kb 44 kb 92 kb
772 kb 236 kb 44 kb
224 kb 0 kb 44 kb [stack]
56 kb 8 kb 40 kb
80 kb 20 kb 36 kb
72 kb 12 kb 24 kb /terminus/crown/bin/ares
928 kb 0 kb 24 kb /usr/lib64/libstdc++.so.6.0.13
10240 kb 0 kb 20 kb
132 kb 0 kb 16 kb
20 kb 0 kb 16 kb
1476 kb 0 kb 16 kb /usr/lib64/libpython2.6.so.1.0
10240 kb 0 kb 12 kb
10240 kb 0 kb 8 kb
16 kb 0 kb 8 kb /usr/lib64/python2.6/lib-dynload/datetime.so
8 kb 0 kb 8 kb /usr/lib64/libstdc++.so.6.0.13
4 kb 0 kb 4 kb /usr/lib64/python2.6/lib-dynload/syslog.so
16 kb 12 kb 4 kb /lib64/libc-2.12.so
4 kb 0 kb 4 kb /lib64/libc-2.12.so
4 kb 0 kb 4 kb /lib64/libm-2.12.so
4 kb 0 kb 4 kb /lib64/libm-2.12.so
28 kb 20 kb 4 kb /usr/lib64/libstdc++.so.6.0.13
84 kb 8 kb 4 kb
92 kb 0 kb 4 kb /lib64/libpthread-2.12.so
4 kb 0 kb 4 kb /lib64/libpthread-2.12.so
4 kb 0 kb 4 kb /lib64/libpthread-2.12.so
16 kb 0 kb 4 kb
12 kb 4 kb 4 kb /usr/lib64/libcurl.so.4.1.1
128 kb 0 kb 4 kb /lib64/ld-2.12.so
4 kb 0 kb 4 kb /lib64/ld-2.12.so
4 kb 4 kb 0 kb /usr/lib64/python2.6/lib-dynload/_randommodule.so
8 kb 8 kb 0 kb /usr/lib64/python2.6/lib-dynload/timemodule.so
4 kb 4 kb 0 kb /usr/lib64/python2.6/lib-dynload/_functoolsmodule.so
4 kb 4 kb 0 kb /usr/lib64/python2.6/lib-dynload/_json.so
4 kb 4 kb 0 kb /lib64/librt-2.12.so
16 kb 8 kb 0 kb /usr/local/boost149/lib/libboost_python.so.1.49.0
4 kb 4 kb 0 kb /usr/local/boost149/lib/libboost_system.so.1.49.0
8 kb 4 kb 0 kb /usr/local/boost149/lib/libboost_thread.so.1.49.0
16 kb 16 kb 0 kb /usr/local/lib/libzmq.so.1.0.0
12 kb 4 kb 0 kb
4 kb 4 kb 0 kb /lib64/ld-2.12.so
4 kb 4 kb 0 kb
SHARED MAPPINGS
vmsize rss clean rss dirty file
4048 kb 948 kb 0 kb /terminus/crown/bin/ares
1476 kb 784 kb 0 kb /usr/lib64/libpython2.6.so.1.0
1576 kb 448 kb 0 kb /lib64/libc-2.12.so
324 kb 172 kb 0 kb /usr/lib64/libcurl.so.4.1.1
928 kb 160 kb 0 kb /usr/lib64/libstdc++.so.6.0.13
524 kb 104 kb 0 kb /lib64/libm-2.12.so
192 kb 76 kb 0 kb /usr/local/lib/libzmq.so.1.0.0
64 kb 32 kb 0 kb /usr/lib64/python2.6/lib-dynload/datetime.so
72 kb 28 kb 0 kb /terminus/crown/bin/ares
92 kb 28 kb 0 kb /lib64/libpthread-2.12.so
312 kb 20 kb 0 kb /usr/local/boost149/lib/libboost_python.so.1.49.0
12 kb 12 kb 0 kb /usr/lib64/python2.6/lib-dynload/_json.so
96 kb 12 kb 0 kb /usr/local/boost149/lib/libboost_thread.so.1.49.0
128 kb 12 kb 0 kb /lib64/ld-2.12.so
8 kb 8 kb 0 kb /usr/lib64/python2.6/lib-dynload/syslog.so
12 kb 8 kb 0 kb /usr/lib64/python2.6/lib-dynload/_randommodule.so
12 kb 8 kb 0 kb /usr/lib64/python2.6/lib-dynload/timemodule.so
8 kb 8 kb 0 kb /usr/lib64/python2.6/lib-dynload/_functoolsmodule.so
28 kb 4 kb 0 kb /lib64/librt-2.12.so
8 kb 4 kb 0 kb /usr/local/boost149/lib/libboost_system.so.1.49.0
4 kb 4 kb 0 kb [vdso]
</pre>
从上面看到rss大小被分成了两个部分: private(私有)和shared(共享).
private rss就是我们最关心的进程实际占用的内存数.