python编程实例-统计apache进程占用的物理内存

 #!/usr/bin/env python

 import os
 from subprocess import PIPE,Popen

 def getPids():
         p = Popen(['pidof','httpd'],stdout=PIPE,stderr=PIPE)
         pids = p.stdout.read().split()
         return pids

 def parsePidFile(pids):
         http_sum = 0
         for i in pids:
                 fn = os.path.join('/proc/',i,'status')
                 with open(fn) as fd:
                         for line in fd:
                                 if line.startswith('VmRSS'):
                                         http_mem = int(line.split()[1])
                                         http_sum += http_mem
                                         break
         return http_sum

 def total_mem(f):
         with open(f) as fd:
                 for line in fd:
                         if line.startswith('MemTotal'):
                                 total_sum = int(line.split()[1])
                                 return total_sum

 if __name__ == '__main__':
         pids = getPids()
         http_sum = parsePidFile(pids)
         total_sum = total_mem('/proc/meminfo')
         print "Apache memory is %s KB" % http_sum
         print "total memory is %s KB" % total_sum
         print "Percent : %.2f %%" % (http_sum/float(total_sum)*100)