RE: Strange iperf results.
Per a note I got from Ajay, this may be due to wrapping of 32 bit counters
which was fixed in one of
the subsequent releases.
On Mon, 16 Dec 2002, Cottrell, Les wrote:
> I am running iperf as follows:
>
> pinger/load/iperf-snv12-chi2iperf -v
> iperf version 1.62 (24 June 2002) pthreads
> iperf -c 192.91.236.2 -p 5014 -w 32768k -t 60 -i 1 -f M >
pinger/load/iperf-snv12-chi2
>
> The output recorded is as below. The output disagrees with itself. At the
end it reports an aggregate throughput of 40.1MBytes/s, however adding up the
incremental throughputs gives a consierably larger value for both Mbytes
transferred and average throughput. I get similar results (after correcting
from Bytes to bits) if I leave off the -f M option, and if I also use a -i 10
(see below).
>
> ------------------------------------------------------------
> Client connecting to 192.91.236.2, TCP port 5014
> TCP window size: 64.0 MByte (WARNING: requested 32.0 MByte)
> ------------------------------------------------------------
> [ 3] local 198.51.111.54 port 35777 connected with 192.91.236.2 port 5014
> [ ID] Interval Transfer Bandwidth
> [ 3] 0.0- 1.5 sec 51.0 MBytes 34.1 MBytes/sec
> [ 3] 1.5- 2.1 sec 19.3 MBytes 29.8 MBytes/sec
> [ 3] 2.1- 3.0 sec 80.6 MBytes 92.2 MBytes/sec
> [ 3] 3.0- 4.0 sec 109 MBytes 111 MBytes/sec
> [ 3] 4.0- 5.0 sec 107 MBytes 107 MBytes/sec
> [ 3] 5.0- 6.0 sec 111 MBytes 111 MBytes/sec
> [ 3] 6.0- 7.1 sec 115 MBytes 109 MBytes/sec
> [ 3] 7.1- 8.0 sec 118 MBytes 126 MBytes/sec
> [ 3] 8.0- 9.0 sec 105 MBytes 105 MBytes/sec
> [ 3] 9.0-10.0 sec 106 MBytes 106 MBytes/sec
> [ 3] 10.0-11.0 sec 127 MBytes 127 MBytes/sec
> [ 3] 11.0-12.0 sec 105 MBytes 105 MBytes/sec
> [ 3] 12.0-13.0 sec 105 MBytes 105 MBytes/sec
> [ 3] 13.0-14.0 sec 128 MBytes 128 MBytes/sec
> [ 3] 14.0-15.0 sec 105 MBytes 105 MBytes/sec
> [ 3] 15.0-16.0 sec 105 MBytes 105 MBytes/sec
> [ 3] 16.0-17.1 sec 123 MBytes 110 MBytes/sec
> [ 3] 17.1-18.0 sec 111 MBytes 125 MBytes/sec
> [ 3] 18.0-19.0 sec 105 MBytes 105 MBytes/sec
> [ 3] 19.0-20.1 sec 117 MBytes 108 MBytes/sec
> [ ID] Interval Transfer Bandwidth
> [ 3] 20.1-21.0 sec 116 MBytes 126 MBytes/sec
> [ 3] 21.0-22.0 sec 105 MBytes 105 MBytes/sec
> [ 3] 22.0-23.0 sec 112 MBytes 107 MBytes/sec
> [ 3] 23.0-24.0 sec 121 MBytes 127 MBytes/sec
> [ 3] 24.0-25.0 sec 105 MBytes 105 MBytes/sec
> [ 3] 25.0-26.0 sec 108 MBytes 106 MBytes/sec
> [ 3] 26.0-27.0 sec 124 MBytes 127 MBytes/sec
> [ 3] 27.0-28.0 sec 105 MBytes 105 MBytes/sec
> [ 3] 28.0-29.0 sec 105 MBytes 105 MBytes/sec
> [ 3] 29.0-30.0 sec 128 MBytes 128 MBytes/sec
> [ 3] 30.0-31.0 sec 104 MBytes 104 MBytes/sec
> [ 3] 31.0-32.0 sec 105 MBytes 105 MBytes/sec
> [ 3] 32.0-33.1 sec 125 MBytes 110 MBytes/sec
> [ 3] 33.1-34.0 sec 106 MBytes 123 MBytes/sec
> [ 3] 34.0-35.0 sec 105 MBytes 105 MBytes/sec
> [ 3] 35.0-36.1 sec 122 MBytes 110 MBytes/sec
> [ 3] 36.1-37.0 sec 111 MBytes 125 MBytes/sec
> [ 3] 37.0-38.0 sec 105 MBytes 105 MBytes/sec
> [ 3] 38.0-39.1 sec 120 MBytes 109 MBytes/sec
> [ 3] 39.1-40.0 sec 111 MBytes 124 MBytes/sec
> [ ID] Interval Transfer Bandwidth
> [ 3] 40.0-41.0 sec 105 MBytes 105 MBytes/sec
> [ 3] 41.0-42.1 sec 119 MBytes 109 MBytes/sec
> [ 3] 42.1-43.0 sec 114 MBytes 126 MBytes/sec
> [ 3] 43.0-44.0 sec 105 MBytes 105 MBytes/sec
> [ 3] 44.0-45.0 sec 112 MBytes 107 MBytes/sec
> [ 3] 45.0-46.0 sec 121 MBytes 127 MBytes/sec
> [ 3] 46.0-47.0 sec 105 MBytes 105 MBytes/sec
> [ 3] 47.0-48.0 sec 109 MBytes 106 MBytes/sec
> [ 3] 48.0-49.0 sec 123 MBytes 126 MBytes/sec
> [ 3] 49.0-50.0 sec 104 MBytes 104 MBytes/sec
> [ 3] 50.0-51.0 sec 111 MBytes 106 MBytes/sec
> [ 3] 51.0-52.0 sec 122 MBytes 127 MBytes/sec
> [ 3] 52.0-53.0 sec 105 MBytes 105 MBytes/sec
> [ 3] 53.0-54.0 sec 105 MBytes 105 MBytes/sec
> [ 3] 54.0-55.1 sec 127 MBytes 111 MBytes/sec
> [ 3] 55.1-56.0 sec 106 MBytes 124 MBytes/sec
> [ 3] 56.0-57.0 sec 105 MBytes 105 MBytes/sec
> [ 3] 57.0-58.1 sec 122 MBytes 110 MBytes/sec
> [ 3] 58.1-59.0 sec 110 MBytes 124 MBytes/sec
> [ 3] 59.0-60.0 sec 104 MBytes 104 MBytes/sec
> [ ID] Interval Transfer Bandwidth
> [ 3] 0.0-60.7 sec 2433 MBytes 40.1 MBytes/sec
>
> iperf -c 192.91.236.2 -p 5014 -w 32768k -f M -t 60 -i 10 >
pinger/load/iperf-snv12-chi2
> ------------------------------------------------------------
> Client connecting to 192.91.236.2, TCP port 5014
> TCP window size: 64.0 MByte (WARNING: requested 32.0 MByte)
> ------------------------------------------------------------
> [ 3] local 198.51.111.54 port 35782 connected with 192.91.236.2 port 5014
> [ ID] Interval Transfer Bandwidth
> [ 3] 0.0-10.0 sec 679 MBytes 67.9 MBytes/sec
> [ 3] 10.0-20.1 sec 1118 MBytes 111 MBytes/sec
> [ 3] 20.1-30.1 sec 1098 MBytes 109 MBytes/sec
> [ 3] 30.1-40.0 sec 1115 MBytes 113 MBytes/sec
> [ 3] 40.0-50.0 sec 1116 MBytes 112 MBytes/sec
> [ 3] 50.0-60.0 sec 1120 MBytes 112 MBytes/sec
> [ 3] 0.0-60.7 sec 2150 MBytes 35.4 MBytes/sec
>
--
Mitch Kutzko | mitch --at-- dast.nlanr.net | mitch --at-- ncsa.uiuc.edu | 217-333-1199
http://hobbes.ncsa.uiuc.edu/