def get_delays(url):
rd = []
nd = []
ad = []
i = 0
#Iterate 5 times
while i<5:
#tcpdump = subprocess.Popen('tcpdump \'tcp[13] & 2 != 0 \' -i eth0 -c 2 -ttt -n', shell=True, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
p = pcapture.capture()
p.filter('tcp[13] & 2 != 0') #Only capture packets that contain a SYN flag
start = time.time() #Before HTTP GET
#Issue HTTP GET with a connect time out of 10 seconds and a read timeout of 10 seconds, and wait for process to finish
wget = subprocess.Popen('wget --connect-timeout=10 --read-timeout=10 -O /dev/null %s'%url,shell=True,stdout=subprocess.PIPE, stderr=subprocess.PIPE)
wget.wait()
end = time.time() #After HTTP GET
#readtcp = tcpdump.communicate()
k = 0
packet = ''
while True: #Look for a packet with a SYN flag only
packet = p.next()
if(packet != None):
if len(packet)>2:
if type(packet[2]) == pycap.protocol.tcp:
if packet[2].flags == 2:
break
SYN = packet
while True: #Look for a packet with SYN+ACK flag
packet = p.next()
if(packet != None):
if len(packet)>2:
if type(packet[2]) == pycap.protocol.tcp:
if packet[2].flags == 18:
break
ACK = packet
rd.append((end-start)) #RD portion of the Document Fetch Delay
first = float(SYN[-1]) #SYN Packet time
last = float(ACK[-1]) #SYN+ACK Packet Time
SYNACK = (last-first)*1.0/1000 #Network Delay
nd.append(SYNACK)
start = time.time() #Before HTTP HI
#Issue HTTP HI (dummy) method with a maximum process time of 20 seconds, and wait for the process to finish. The no-keepalive ensures that persistent connection is off
curl = subprocess.Popen('curl -m 20 --no-keepalive -sLX HI %s -o /dev/null'%url,shell=True,stdout=subprocess.PIPE, stderr=subprocess.PIPE)
curl.wait()
end = time.time() #After HTTP HI
ad.append((end-start)) #AD portion of the Processing Delay
i+=1
print 'done with iteration %d'%i
delays = []
dfd = []
pd = []
i = 0
while i<5:
dfd.append(rd[i]-nd[i]) #DFD = RD - ND
pd.append(ad[i]-nd[i]) #PD = AD - ND
i+=1
delays.append(nd)
delays.append(dfd)
delays.append(pd)
return delays
Opts, Args = parser.parse_args() Opts.logfd = sys.stdout act = Action.instance() reqcache = HTTP_ReqCache(act) # timeout requests from the cache on a regular basis def check_cache(signum, _): reqcache.check(time.time()) signal.signal(signal.SIGALRM, check_cache) signal.setitimer(signal.ITIMER_REAL, reqcache.max_age_sec, 1) capargs = opts2capargs(Opts) try: p = cap.capture(**capargs) except Exception as e: print e if 'no suitable device found' in str(e): if not hasattr(os, 'geteuid') or os.geteuid() != 0: print >> sys.stderr, 'try running as root' exit(1) try: while True: try: packet = p.next() except prot.error, e: print e continue # we assume HTTP will be: eth:ip:tcp:http:timestamp if not packet or len(packet) != 5:
from pycap import capture
cap = capture.capture('wlan0')
while True:
aa = cap.next()
try:
if aa[1].version == 6:
print aa[1].version
import ipdb; ipdb.set_trace()
except:
pass
