ndt-users list created

[Maurice Volaski <>]

Hi Rich,

I don't think I ever heard back from you regarding this. The test I'm 
running below was run directly from my Mac Pro. I just ran it again 
on 10.5 and got a similar result.

> At 2:52 PM -0500 1/17/08, Maurice Volaski wrote:
> > Hi Maurice;
> >
> > Thanks for the info.  I'm sure others will be trying VM instances 
> > and it will be good to document that there may be issues with the 
> > Lance driver.
> >
> > The tcpdump and snaplog files may give me some insight into the 10 
> > Mbps link reporting problem.  If its not too much trouble, then 
> > send me those logs.  Otherwise I'll work on my Xen VM host.
>
> Sorry to take so long. Seems the bad duplex condition has returned 
> again. Here's all the info.
>
> WEB100 Enabled Statistics:
> Checking for Middleboxes . . . . . . . . . . . . . . . . . .  Done
> checking for firewalls . . . . . . . . . . . . . . . . . . .  Done
> running 10s outbound test (client-to-server [C2S]) . . . . . 250.62Mb/s
> running 10s inbound test (server-to-client [S2C]) . . . . . . 55.70Mb/s
>
>         ------  Client System Details  ------
> OS data: Name = Mac OS X, Architecture = i386, Version = 10.5
> Java data: Vendor = Apple Inc., Version = 1.5.0_13
>
>         ------  Web100 Detailed Analysis  ------
> 10 Mbps Ethernet link found.
> Link set to Full Duplex mode
> No network congestion discovered.
> Good network cable(s) found
> Warning: Old Duplex mismatch condition detected:
> Web100 reports the Round trip time = 1.03 msec; the Packet size = 
> 1448 Bytes; and
> There were 6030 packets retransmitted, 12166 duplicate acks 
> received, and 18216 SACK blocks received
> The connection stalled 42 times due to packet loss
> The connection was idle 8.57 seconds (85.7%) of the time
> S2C throughput test: Packet queuing detected: 0.96%
> This connection is sender limited 6.22% of the time.
> This connection is network limited 93.78% of the time.
>
> Web100 reports TCP negotiated the optional Performance Settings to:
> RFC 2018 Selective Acknowledgment: ON
> RFC 896 Nagle Algorithm: ON
> RFC 3168 Explicit Congestion Notification: OFF
> RFC 1323 Time Stamping: ON
> RFC 1323 Window Scaling: ON
>
> Server '129.98.90.16' is not behind a firewall. [Connection to the 
> ephemeral port was successful]
> Client is not behind a firewall. [Connection to the ephemeral port 
> was successful]
> Information: Network Middlebox is modifying MSS variable
> Server IP addresses are preserved End-to-End
> Client IP addresses are preserved End-to-End
>
>
> WEB100 Kernel Variables:
> Client: localhost/127.0.0.1
> X_Rcvbuf: 212992
> X_Sndbuf: 212992
> AckPktsIn: 33177
> AckPktsOut: 0
> BytesRetrans: 8723064
> CongAvoid: 0
> CongestionOverCount: 33
> CongestionSignals: 99
> CountRTT: 20209
> CurCwnd: 24616
> CurMSS: 1448
> CurRTO: 204
> CurRwinRcvd: 524280
> CurRwinSent: 5792
> CurSsthresh: 21720
> DSACKDups: 0
> DataBytesIn: 0
> DataBytesOut: 80661336
> DataPktsIn: 0
> DataPktsOut: 55981
> DupAcksIn: 12166
> ECNEnabled: 0
> FastRetran: 57
> MaxCwnd: 123080
> MaxMSS: 1448
> MaxRTO: 208
> MaxRTT: 8
> MaxRwinRcvd: 524280
> MaxRwinSent: 5792
> MaxSsthresh: 97016
> MinMSS: 1448
> MinRTO: 204
> MinRTT: 0
> MinRwinRcvd: 205672
> MinRwinSent: 5792
> NagleEnabled: 1
> OtherReductions: 502
> PktsIn: 33177
> PktsOut: 55981
> PktsRetrans: 6030
> RcvWinScale: 4
> SACKEnabled: 3
> SACKsRcvd: 18216
> SendStall: 0
> SlowStart: 0
> SampleRTT: 0
> SmoothedRTT: 4
> SndWinScale: 3
> SndLimTimeRwin: 0
> SndLimTimeCwnd: 9585093
> SndLimTimeSender: 636072
> SndLimTransRwin: 0
> SndLimTransCwnd: 426
> SndLimTransSender: 427
> SndLimBytesRwin: 0
> SndLimBytesCwnd: 57727304
> SndLimBytesSender: 22934032
> SubsequentTimeouts: 0
> SumRTT: 20772
> Timeouts: 42
> TimestampsEnabled: 1
> WinScaleRcvd: 3
> WinScaleSent: 4
> DupAcksOut: 0
> StartTimeUsec: 562542
> Duration: 10229166
> c2sData: 3
> c2sAck: 3
> s2cData: 3
> s2cAck: 3
> half_duplex: 0
> link: 0
> congestion: 0
> bad_cable: 0
> mismatch: 1
> spd: 63.13
> bw: 255.58
> loss: 0.001768457
> avgrtt: 1.03
> waitsec: 8.57
> timesec: 10.00
> order: 0.3667
> rwintime: 0.0000
> sendtime: 0.0622
> cwndtime: 0.9378
> rwin: 3.9999
> swin: 1.6250
> cwin: 0.9390
> rttsec: 0.001028
> Sndbuf: 212992
> aspd: 0.00000
> CWND-Limited: 144182.65
> minCWNDpeak: 4344
> maxCWNDpeak: 46336
> CWNDpeaks: 17
>
> The theoretical network limit is 255.58 Mbps
> The NDT server has a 104.0 KByte buffer which limits the throughput 
> to 1580.73 Mbps
> Your PC/Workstation has a 511.0 KByte buffer which limits the 
> throughput to 3890.95 Mbps
> The network based flow control limits the throughput to 913.42 Mbps
>
> Client Data reports link is 'Ethernet', Client Acks report link is 'Ethernet'
> Server Data reports link is 'Ethernet', Server Acks report link is 'Ethernet'

--

Maurice Volaski, 

Computing Support, Rose F. Kennedy Center
Albert Einstein College of Medicine of Yeshiva University