安装systemtap

按照官网说的安装：

我的操作系统是centos

uname -rm:

2.6.18-164.el5xen x86_64

yum install systemtap

wget

[root@test34x-nova ~/software]# rpm -Uhv kernel-debuginfo-*rpm

warning: kernel-debuginfo-2.6.18-164.el5.x86_64.rpm: Header V3 DSA signature: NOKEY, key ID e8562897

Preparing... ########################################### [100%]

1:kernel-debuginfo-common########################################### [ 50%]

2:kernel-debuginfo ########################################### [100%]

测试是否安装成功

stap -ve 'probe begin { log("hello world") exit() }'

提示：

Checking "/lib/modules/2.6.32-279.el6.x86_64/build/.config" failed with error: 没有那个文件或目录

Incorrect version or missing kernel-devel package, use: yum install kernel-devel-2.6.32-279.el6.x86_64

下载Flame Graph

比如我放在这个目录里：

/home/yejianfeng/software/FlameGraph-master

下面拿nginx的一个模块来进行测试

这里有个自己写的mysecret2的模块

安装配置好，确保能访问

写一个systemtrap脚本：

                         
global
s;
global
quit = 0;
probe timer.profile { 
if
(pid() == target()) { 
if
(quit) { 
foreach
(i in s-) { 
print_ustack(i);
printf(
"\t%d\n"
, @
count
(s[i]));
}
exit
;
} 
else
{ 
s[ubacktrace()] <<< 1;
}
}
}
probe timer.s(20) { 
quit = 1;
}
        
      

                         
<P>[root@test34x-nova ~/handcode]# stap --ldd -d 
/home/yejianfeng/nginx/nginx/sbin/nginx --all-modules -D MAXMAPENTRIES=256 -D 
MAXACTION=20000 -D MAXTRACE=100 -D MAXSTRINGLEN=4096 -D MAXBACKTRACE=100 -x 
26150 /home/yejianfeng/handcode/ngx.stp --vp 0001 &gt; 
/home/yejianfeng/ngx.out&nbsp;
<P>WARNING: never-assigned local variable 
'exit'
(alternatives: i s quit): 
identifier 
'exit'
at /home/yejianfeng/handcode/ngx.stp:10:4
<P>&nbsp;source: 
exit
;
<P>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; ^
<P>WARNING: Eliding side-effect-free expression : identifier 
'exit'
at :10:4
<P>&nbsp;source: 
exit
;
<P>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; ^
<P>WARNING: missing unwind/symbol data 
for
module 
'kernel'
<P>WARNING: missing unwind/symbol data 
for
module 
'uprobes'
<P>Pass 4: compiled C into 
"stap_7ee66ba3cf5480d819b30e4f49bf3bb1_3633.ko"
in 
5560usr/1320sys/9525real ms.
<P>WARNING: /usr/bin/staprun exited with status: 1
<P>Pass 5: run failed. &nbsp;Try again with another 
'--vp 00001'
option.</P>
        
      

纯笔记。。。搞了半天没搞出来。。。MMD。。。水平太搓了。。。