ganglia对于tomcat进程的res内存监控扩展

ganglia是采用yum的安装，因此安装相关内容路径可能不同，但是不影响插件的扩展编写；

本次介绍的扩展是采用python脚本进行扩展，因此监控节点上需要安装python的相关插件；

sudo yum -y install  ganglia-gmond-python  python-devel*

由于脚本要引入psutil的库，因此需要加载此模块，安装此模块需要首先按装gcc和pip

sudo yum -y install gcc python-pip

最后安装psutil模块

sudo pip install psutil

一般进入ganglia的python脚本模块，编写脚本

 路径一般为： /usr/lib64/ganglia/python_modules，新建脚本编辑，vi tomcat_mem.py

#encoding=utf-8
import psutil
import time
import sys
import commands
#获取tomcat的id进程号
commandLine1="sudo ps -ef | grep tomcat | grep -v grep|grep -v python | awk '{print $2}'";
(status,pid)=commands.getstatusoutput(commandLine1)
print pid
dscriptors = list()

def tomcat_res(name):
    p=psutil.Process(int(pid))
    return int((p.memory_info()[0]))
def metric_init(params):
    global descriptors
    d1 ={
    "name":"tomcat_res",
    "call_back":tomcat_res,
    "time_max":90,
    "value_type":"uint",
    "units": "memory info",
    "slope":"both",
    "format":"%u",
    "description": "",
    "groups":"tomcat",
    }
    descriptors = [d1]
    return descriptors

def metric_cleanup():
    pass

#This code is for debugging and unit testing
if __name__=='__main__':
    metric_init('init')
    for d in descriptors:
        v=d["call_back"](d["name"])
        print 'value for %s is %u '%(d["name"],v)

在到配置目录下，vi /etc/ganglia/conf.d/tomcat.pyconf,前提是已经配置好了modpython.conf

 modules{
     module{
         name="tomcat_mem"
         language="python"
     }
 }

 collection_group{
     collect_every = 2
     time_threshold =90
     metric{
     name="tomcat_res"
     title="tomcat memory"
     value_threshold = 0
     }
 }

modpython.conf

 /*
   params - path to the directory where mod_python
            should look for python metric modules

   the "pyconf" files in the include directory below
   will be scanned for configurations for those modules
 */
 modules {
   module {
     name = "python_module"
     path = "modpython.so"
     params = "/usr/lib64/ganglia/python_modules"
   }
 }

 include ("/etc/ganglia/conf.d/*.pyconf")

 这个有一个缺点就是，tomcat挂了以后重启，ganglia就获取不到数据，需要重启gmond进程，原因目前未知；