An example:
Suppose 13 and 14 are online machines, 148 is a target machine which
is similar to
the online machines, and 12321 is used both as local port and remote
port. We
use tcpcopy to test if 148 can endure two times of current online
stress.
Using tcpcopy to perform the above test task.
the target machine(148)
# modprobe ip_queue (if not run up)
# iptables -I OUTPUT -p tcp --sport 12321 -j QUEUE (if not set)
# ./interception
online machine(13):
# ./tcpcopy xx.xx.xx.13 12321 xx.xx.xx.148 12321
online machine(14):
# ./tcpcopy xx.xx.xx.14 12321 xx.xx.xx.148 12321
Cpu load and memory usage are as follows:
13 cpu:
11124 adrun 15 0 193m 146m 744 S 18.6 7.3 495:31.56
Name:
tcpcopy
It is a request replication tool and is mainly for testing tasks
using netlink and raw sockets
Description:
It can help you find bugs in your online project without actually
being online.
And it can also be used to test the stress that a system could
endure.
For example, if your system already has "memcached" subsystem and
you want to
use “membase” to replace it, tcpcopy can assist you to test
“membase”. While your
old memcached system is still running online, tcpcopy could copy the
flow of packets
from memcached to membase. From the point view of membase, the flow
is accessing
membase(just like membase online), and it will not affect memcached
at all except
network bandwidth and a little cpu load.
Functionalities:
1) Distributed Stress Test
You can use online data to test the stress that your target
machine can endure. It is better
than apache ab tool and you can find bugs that only occur during
high-stress situations.
2) Hot Backup
It is very suitable for backup tasks if connections are
short-lived and the request loss rate
is very low(1/100000).
3) Normal Online Test
You can find whether the new system is stable and find bugs that
only occur in actual
online environments.
4) Comparison Test
For example, you can use tcpcopy to compare the performances of
apache and nginx.
Characteristics:
1)real time
2)realistic
3)efficient
4)easy to use
5)distributed
6)significant