Skip to content

Instantly share code, notes, and snippets.

Embed
What would you like to do?
Assessing pending activity of a Redis server
> ~/tcp_redis_monitor.py 6379
Timestamp Nb TX bytes RX bytes TX RMA RX RMA
1333983822.943 1 0 0 0.000 0.000
1333983823.193 1 0 0 0.000 0.000
1333983824.194 1 0 0 0.000 0.000
1333983825.195 1 0 0 0.000 0.000
1333983826.196 1 0 0 0.000 0.000
>> Starting redis-benchmark with some pipelining
>> The client box is way slower than the server box, so transmit buffers are used
1333983827.197 197 27020 360 15739.062 90.000
1333983828.198 197 27440 0 23663.922 58.008
1333983829.200 261 26110 0 25830.694 18.354
1333983830.201 182 25060 280 24926.614 128.307
1333983831.202 182 25060 0 25052.249 70.128
1333983832.203 293 20323 0 23994.704 22.189
1333983833.205 201 20000 0 21161.996 7.021
1333983834.206 201 20000 0 20297.350 377.221
1333983835.207 201 20000 0 20056.584 494.355
1333983836.208 201 9900 6560 16873.544 1902.636
1333983837.209 201 35460 820 29794.285 893.490
1333983838.210 201 35820 820 33991.473 487.706
1333983839.211 201 36000 0 35320.193 356.110
1333983840.212 186 37000 0 33447.827 1061.660
1333983841.213 186 37000 0 35838.570 508.416
1333983842.214 186 36800 0 36519.235 160.866
>> Running redis-cli debug sleep 20
>> which freezes the Redis event loop for 20 secs
>> Now incoming traffic is accumulating in the receive buffers
1333983843.215 202 15000 101200 31235.383 25868.399
1333983844.216 202 0 184015 9883.070 133577.521
1333983845.218 202 0 184015 3127.065 168056.266
1333983846.219 202 0 184015 989.423 178965.557
1333983847.220 202 0 184015 313.060 182417.325
1333983848.221 202 0 184015 99.054 183509.486
1333983849.222 202 0 184015 31.341 183855.052
1333983850.223 202 0 184015 9.917 183964.391
1333983851.224 202 0 184015 3.138 183998.987
1333983852.225 202 0 184015 0.993 184009.933
1333983853.226 202 0 184015 0.314 184013.397
1333983854.227 202 0 184015 0.099 184014.493
1333983855.229 202 0 184015 0.031 184014.840
1333983856.230 202 0 184015 0.010 184014.949
1333983857.231 202 0 184015 0.003 184014.984
1333983858.232 202 0 184015 0.001 184014.995
1333983859.233 202 0 184015 0.000 184014.998
1333983860.234 202 0 184015 0.000 184014.999
1333983861.235 202 0 184015 0.000 184015.000
1333983862.236 202 0 184015 0.000 184015.000
>> End of the freeze
1333983863.237 201 40000 0 17500.000 103508.437
1333983864.238 264 31814 0 30834.359 32750.717
1333983865.239 182 36200 0 33647.055 10362.531
1333983866.240 182 35800 0 35205.514 3515.020
1333983867.241 201 36200 0 35885.338 1112.174
1333983868.242 201 36000 0 32769.752 554.399
1333983869.243 201 35820 0 34880.195 230.259
1333983870.244 201 36000 0 35533.890 170.355
1333983871.245 272 29330 0 34087.989 127.027
1333983872.246 201 16000 0 21503.883 280.661
1333983873.248 201 16000 0 17718.963 409.428
1333983874.249 201 16000 0 16502.641 129.546
1333983875.250 201 14754 0 15847.539 40.989
1333983876.000 201 20000 0 16715.368 157.917
1333983877.001 201 20000 0 18927.909 214.029
1333983878.002 201 20000 0 19598.674 307.954
1333983879.004 201 39400 0 26906.924 97.439
>> End of the benchmark
1333983880.005 1 0 0 13894.394 30.830
1333983881.006 1 0 0 4396.273 9.755
1333983882.007 1 0 0 1391.008 3.087
1333983883.008 1 0 0 440.124 0.977
1333983884.009 1 0 0 139.258 0.309
1333983885.010 1 0 0 44.062 0.098
1333983886.012 1 0 0 13.942 0.031
1333983887.013 1 0 0 4.411 0.010
1333983888.014 1 0 0 1.396 0.003
1333983889.015 1 0 0 0.442 0.001
1333983890.016 1 0 0 0.140 0.000
1333983891.018 1 0 0 0.044 0.000
#!/usr/bin/env python
# ---------------------------------------------------------
import sys,time, math
# ---------------------------------------------------------
class ProcReader:
"""
Format of /proc/net/tcp
46: 010310AC:9C4C 030310AC:1770 01
| | | | | |--> connection state
| | | | |------> remote TCP port number
| | | |-------------> remote IPv4 address
| | |--------------------> local TCP port number
| |---------------------------> local IPv4 address
|----------------------------------> number of entry
00000150:00000000 01:00000019 00000000
| | | | |--> number of unrecovered RTO timeouts
| | | |----------> number of jiffies until timer expires
| | |----------------> timer_active (see below)
| |----------------------> receive-queue
|-------------------------------> transmit-queue
1000 0 54165785 4 cd1e6040 25 4 27 3 -1
| | | | | | | | | |--> slow start size threshold,
| | | | | | | | | or -1 if the threshold
| | | | | | | | | is >= 0xFFFF
| | | | | | | | |----> sending congestion window
| | | | | | | |-------> (ack.quick<<1)|ack.pingpong
| | | | | | |---------> Predicted tick of soft clock
| | | | | | (delayed ACK control data)
| | | | | |------------> retransmit timeout
| | | | |------------------> location of socket in memory
| | | |-----------------------> socket reference count
| | |-----------------------------> inode
| |----------------------------------> unanswered 0-window probes
|---------------------------------------------> uid
"""
def __init__(self,port):
self.port = port
self.f = open( "/proc/net/tcp" )
self.porthex = ":%04X" % (port)
def read(self):
now = time.time()
self.f.seek(0)
lines = self.f.readlines()
n, sum_tx, sum_rx = 0, 0, 0
for line in lines:
t = line.split()
if not t[1].endswith(self.porthex):
continue
x = t[4].split(':')
n += 1
sum_tx += int(x[0],16)
sum_rx += int(x[1],16)
return now,sum_tx,sum_rx,n
# ---------------------------------------------------------
def main(port):
"""
Display: timestamp
nb sockets
tx = pending data to transmit for all connections (bytes)
rx = pending data to receive for all connections (bytes)
running moving average of tx (1 sec, 4 points)
running moving average of rx (1 sec, 4 points)
"""
p = ProcReader(port)
t, tx, rx = 0.0, 0.0, 0.0
print "%16s %6s %12s %12s %16s %16s" % ( "Timestamp", "Nb", "TX bytes", "RX bytes", "TX RMA", "RX RMA" )
while 1:
x = p.read()
tx = (3*tx+x[1])/4
rx = (3*rx+x[2])/4
if int(x[0]) != t:
print "%16.3f %6d %12d %12d %16.3f %16.3f" % (x[0],x[3],x[1],x[2],tx,rx)
t = int(x[0])
time.sleep(0.250-(time.time()-x[0]))
# ---------------------------------------------------------
if len(sys.argv) != 2:
sys.stderr.write( "Usage: %s port\n" % (sys.argv[0]) )
sys.exit( -1 )
main( int(sys.argv[1]) )
# ---------------------------------------------------------
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
You can’t perform that action at this time.