网络速率统计的几个示例

最近新换了工作，新公司是一家做通信领域的公司(baicells)。虽然仍旧是从事测试开发相关的工作，但通信领域毕竟是新手，所以最近一直在恶补相关基础知识，耽误了文章的更新。

本文主要分享几个系统下统计网络速率的几个小方法，供参考。

1.网络设备

该方法比较简单直接，不借助其他工具，直接读取一定时间间隔的网络收发数据量，然后进行速率计算。优点是简单粗暴，通用性比较强。缺点只能按照网络设备进行统计，不能按照接口进行划分。

代码如下：

#!/usr/bin/env pythrn
# *-* coding=utf-8 *-*

import time
import sys
import os
from optparse import OptionParser


def recive_args():
    parser = OptionParser()
    parser.add_option("-m", "--mode", dest="mode",
                      help="mode")
    parser.add_option("-t", "--time",dest="time",
                      help="time")
    (options, args) = parser.parse_args()
    test_args = {}
    test_args["mode"] = options.mode
    test_args["time"] = options.time
    return test_args


class NetRate:
    def __init__(self, time, mode):
        self.time=int(time)
        self.mode=mode

    def rx(self):
        totalrx = []
        try:
            ifstat = open('/proc/net/dev').readlines()
            for i,interface in enumerate(ifstat):
                stat = interface.split()
                if i >= 3:
                    totalrx.append(stat)
            rxdata = 0
            for rxtmp in totalrx:
                rxdata += float(rxtmp[1])
            return rxdata
        except:
            return 0

    def tx(self):
        totaltx = []
        try:
            ifstat = open('/proc/net/dev').readlines()
            for i,interface in enumerate(ifstat):
                print ifstat
                stat = interface.split()
                if i >= 3:
                    totaltx.append(stat)
            txdata = 0
            for txtmp in totaltx:
                txdata += float(txtmp[9])
            return txdata
        except:
            return 0

    def run(self):
        if self.mode == "RX":
            beforerx = self.rx()
            time.sleep(self.time)
            afterrx = self.rx()
            return (afterrx - beforerx) * 8 / self.time
        else:
            beforetx = self.tx()
            time.sleep(self.time)
            aftertx = self.tx()
            return (aftertx - beforetx) * 8 / self.time


args = recive_args()
test = NetRate(args["time"], args["mode"])
rate = test.run()

代码比较简单，不再分析哈，主要时间不多。

2. TCPdump

下面这个方法，是调用tcpdump工具，进行速率统计，tcpdump是比较常用的网络分析工具。优点：可以按照端口进行统计缺点：速率太高时，由于tcpdump打印过快，碍于python执行效率问题（更大可能是博主水平问题哈），速率统计可能不太准确

代码如下：

#!/usr/bin/env python
#*-*coding=utf-8*-*
import re,sys
import time
import os
import subprocess
import datetime
import signal
import multiprocessing
import threading
import Queue 
from optparse import OptionParser

def recive_args():
    parser = OptionParser()
    parser.add_option("-i", "--ip", dest="targetip",
                      help="ip")
    parser.add_option("-t", "--time",dest="time",
                      help="time")
    (options, args) = parser.parse_args()
    test_args={}
    test_args["ip"]= options.targetip
    test_args["time"]=options.time
    return test_args


class Getrate:

    def get_rate_ip(self,IP):
        GET_LENGTH = re.compile(r'length (\d+):')
        total = 0
        test=[]
        tcpdump = subprocess.Popen('tcpdump -e -i p1p1 -nn host %s' % IP, shell=True, stdout=subprocess.PIPE)
        for line in iter(tcpdump.stdout.readline, ''):
            rt = GET_LENGTH.findall(line)
            if len(rt):
                total += int(rt[0])
            while not self.result.empty():
                test.append(self.result.get())
            if "TIMEOUT" in test:
                break
        self.result.put((total*8))
        return True

    def getrate(self,IP, times):
        initlog = subprocess.Popen("echo '' > /opt/tcp.log", shell=True)
        self.result =Queue.Queue()
        LOGFILE = open('/opt/tcp.log', 'a')
        t1 =  threading.Thread(target=self.get_rate_ip, name="thread1", args=(IP,))
        t1.start()
        time.sleep(int(times))
        self.result.put("TIMEOUT")
        t1.join()
        result = self.result.get()
        killdump = subprocess.Popen("killall -9 tcpdump", shell=True)
        LOGFILE.write("%s:%s" %(IP, result/int(times)))
        return result/int(times)

if __name__ == '__main__':
    sysargs=recive_args()
    test = Getrate()
    result = test.getrate("192.168.100.103", sysargs["time"])

其他方法

比如借助sar,系统自带的log等

部分代码如下：

sar:

    def _ftp_getrate_sar(self,expectspeed,mode,testtime,ratetime,clientip,
                           netdev,hostname,username, password,
                           port):
        port = int(port)
        testtime=int(testtime)
        ratetime = int(ratetime)
    client=paramiko.SSHClient()
    client.set_missing_host_key_policy(paramiko.AutoAddPolicy())
    client.connect(hostname,port,username, password)
    times = int(ratetime/3)
    if mode == "RX":
        cmd = "sar -n DEV 3 %s | grep Average | grep %s | awk -F ' ' '{print $5}' | tr -d '\n'" % (times,netdev)
    elif mode == "TX":
            cmd = "sar -n DEV 3 %s | grep Average | grep %s | awk -F ' ' '{print $6}' | tr -d '\n'" % (times,netdev)
        else:
            cmd = "sar -n DEV 3 %s | grep Average | grep %s | awk -F ' ' '{print $6 + $5}' | tr -d '\n'" % (times,netdev)
        starttime = time.time()
        time.sleep(ratetime)
    while time.time() - starttime < (testtime-ratetime):
            stdin,stdout,stderr=client.exec_command(cmd)
            testrate = float(stdout.read())
            rate = testrate * 8 * 1024
            print "test rate is %s" %rate
            if rate < expectspeed:
                 self.Status.put("LOW")
                 self.Status_rate.put("LOW")
                 print "test rate is below than expectspeed"
                 return False
        return True

后续会继续总结分享一些工作中用到的测试方法，敬请期待。