Re: Incorrect Throughput Summaries in UDP?
What operating system are you using? It would appear that iperf did not
find a 64bit integer to use as the total amount of traffic. As such you
overflowed your 32bit integer at 4GB.
Kevin
On Thu, 27 Feb 2003, Yee-Ting Li wrote:
> Hello,
>
> We're trying to do some iperf tests through an uncongested network using UDP
> streams, reporting the rate every 2 seconds for 1 minute. We're using iperf
> 1.6.5 with pthreads and we get some strange reporting of the summary result:
>
>
> ------------------------------------------------------------
> Server listening on UDP port 5010
> Receiving 1472 byte datagrams
> UDP buffer size: 2097152 Byte (WARNING: requested 1048576 Byte)
> ------------------------------------------------------------
> [ 3] local xxx.xxx.xxx.xxx port 5010 connected with
> xxx.xxx.xxx.xxx port 32769
> [ ID] Interval Transfer Bandwidth Jitter Lost/Total
> Datagrams
> [ 3] 0.0- 2.0 sec 204248832 Bytes 816993694 bits/sec 0.015 ms
> 41676/180432 (23%)
...
> [ 3] 58.0-60.0 sec 197239168 Bytes 788955489 bits/sec 0.012 ms
> 47441/181435 (26%)
> [ 3] 0.0-60.0 sec 1559126656 Bytes 207849079 bits/sec 0.012 ms
> 1466661/5443627 (27%)
> [ 3] 0.0-60.0 sec 2 datagrams received out-of-order
>
>
>
> As you can see, the summary rate is much smaller than that reported by the
> regular intervals; also, the total number of bytes transfered is about a third
> less than the accumulated count.
>
> We repeated the test a few times and the report is similar in all tests.
>
>
> Any comments/suggestions appreciated!
>
> Yee.
>
>
>
>