Iperf suggestion
Hi,
if you are considering these changes, please also consider the following
that will be useful for network testing:
IPERF_PRE_WAIT_MSEC:
sugessted below already
IPERF_POST_WAIT_MSEC
marginally useful; could do it for consistency.
IPERF_INTER_WAIT_MSEC
useful for simulating a real application that sends for a while,
does work, etc. this should apply for the receiver as well as for
the sender.
the last idea came from the book Steven's TCP/IP book; it had a program
called "sock" that had a number of features, and i thought these would
be particularly useful.
thanks!
--rr
From: SMTP%"cottrell --at-- SLAC.Stanford.EDU" "Cottrell, Les" 3-NOV-2002
09:51:15.16
To: iperf-users --at-- dast.nlanr.net
CC: rreddy --at-- psc.edu
Subj: Iperf suggestion
To more elegantly use web100 with iperf, Raghurama 'REDDY' [rreddy --at-- psc.edu]
has modified iperf as follows. This might be interesting to consider as a
modifiecation to the distributed version.:
>From Raghurama 'REDDY' [rreddy --at-- psc.edu]:
"i have modified iperf slightly so that it waits for some number of seconds
after connect but before actually sending out the data (this is mainly for
the client code; keep in mind this change invalidates the transfer rates
you see on the server, but the
clients side are correct).
the time to wait is determined by the env variable IPERF_PRE_WAIT_MSEC (in
msec):
setenv IPERF_PRE_WAIT_MSEC 2000
this is my modification to PerfSocket_TCP. when i run iperf, it waits for
2 seconds before starting to send the data. within this time, i have a
script that determines the CID based on the port.
here are is what i usually do (getcidbyport is my script that gets the most
recent connection to port 5821, and it waits for 1 second before attempting
to get the CID giving iperf some time to get connected):
------------
kirana% setenv IPERF_PRE_WAIT_MSEC 2000
kirana% iperf -c vh -p 5821 -w 1m & ; gutil vdt ThruBytesAcked
`getcidbyport 5821 1`
[1] 10032
------------------------------------------------------------
Client connecting to vh, TCP port 5821
TCP window size: 2.0 MByte (WARNING: requested 1.0 MByte)
------------------------------------------------------------
Waiting for 2000 msec before starting write ...done
[ 3] local 192.88.115.178 port 36001 connected with 128.182.66.118 port 5821
[ ID] Interval Transfer Bandwidth
[ 3] 0.0-10.0 sec 95.5 MBytes 79.7 Mbits/sec
-------------
hope this helps!"
--
Mitch Kutzko | mitch --at-- dast.nlanr.net | mitch --at-- ncsa.uiuc.edu | 217-333-1199
http://hobbes.ncsa.uiuc.edu/