iperf 1.7.0 observation / question (fwd)
>Jeff King
>Wave Three
>435-787-0555 x103 (office)
>
>
>I have a question
>regarding some iperf 1.7.0 testing I have been doing between
>two directly connected Windows machines (one Win2K and one
>WinXP). They are both connected with 100M full duplex
>connectivity. Same result with multiple switches and
>directly connected with Xover cable.
>
>Test 1) Single UDP stream
>
>Machine 1)
>
>C:\iperf s u i 1
>
>Machine 2)
>
>C:\iperf c 10.2.50.2 u b 10m
>
>Result: This single one way UDP stream works fine
>with either machine in the server or client role;
>little or no data loss.
>
>Test 2) UDP Test in tradeoff mode
>
>Machine 1)
>
>C:\iperf s u i 1
>
>Machine 2)
>
>C:\iperf c 10.2.50.2 u b 10m -r
>
>Result: This works fine, little or no data loss.
>
>Test 3) UDP Test in Dualtest mode
>
>Machine 1)
>
>C:\iperf s u i 1
>
>Machine 2)
>
>C:\iperf c 10.2.50.2 u b 10m d
>
>Result: This results in significant data loss using
>default 1470 byte datagram independent of what machine
>is client or server role.
>
>Test 4) UDP Test in Dualtest mode with large datagram
>
>Machine 1)
>
>C:\iperf s u i 1 l 10000
>
>Machine 2)
>
>C:\iperf c 10.2.50.2 u b 10m d l 10000
>
>Result: This results in little or no data loss in
>either direction.
>
>
>This does not appear to be a speed or duplex problem
>as both ends are in 100/full mode. I see a similar
>problem when increasing the bandwidth to 20m but then
>I have to increase the datagram size even larger to get
>low error rate.
>
>Do you have suggestions as to what you think the problem
>may be as I would think that smaller datagrams would
>not exhibit such a problem?
>
>Thanks for your feedback.
>
>Regards,
>
>Jeff King
>Wave Three
>435-787-0555 x103 (office)
>
--
Mitch Kutzko | mitch --at-- dast.nlanr.net | mitch --at-- ncsa.uiuc.edu | 217-333-1199
http://hobbes.ncsa.uiuc.edu/