NDT-DEV email list created

Status: New
Owner: ----
Labels: Type-Defect Severity-Medium

New issue 51 by sekharnv73: Ifconfig output shows receive packets are  
dropped and the outbound throughput reported is low.
http://code.google.com/p/ndt/issues/detail?id=51

What steps will reproduce the problem?

1. Connect server and client in a 1GBit Switch
2. Start both servers (fakewww and web100)
3. Set the following tcp paramters in client.
        echo 1 > /proc/sys/net/ipv4/tcp_moderate_rcvbuf
        echo 4194304 > /proc/sys/net/core/wmem_max
        echo 4194304 > /proc/sys/net/core/rmem_max
        echo "4096 87380 4194304" > /proc/sys/net/ipv4/tcp_rmem
        echo "4096 16384 4194304" > /proc/sys/net/ipv4/tcp_wmem
        echo "1" > /proc/sys/net/ipv4/tcp_timestamps
        echo "1" > /proc/sys/net/ipv4/tcp_window_scaling
        echo "1" > /proc/sys/net/ipv4/tcp_sack
        echo "0" > /proc/sys/net/ipv4/tcp_ecn

4. Check the ifconfig output.
5. Click the start button to start the test and wait till client complete
   the test.
6. Check the ifconfig output.

What is the expected output? What do you see instead?
Outbound throughput should be around 1Gbit but the throughput reported is  
in the range 470Mbit to 700Mbit. Ifconfig output show RX packet drop.




What version of the product are you using? On what operating system?
NDT server 3.6.3
Client : Linux (Ubuntu 9)


Please use labels and text to provide additional information.


Attachments:
        outbound_throughput.png  194 KB
        packetdrop_ifconfig.png  135 KB