Kallol Biswas <firstname.lastname@example.org> writes:
> Over a half duplex 10Mbps connection:
> TCP STREAM TEST to 18.104.22.168
> Recv Send Send Utilization Service Demand
> Socket Socket Message Elapsed Send Recv Send Recv
> Size Size Size Time Throughput local remote local remote
> bytes bytes bytes secs. 10^6bits/s % L % L us/KB us/KB
> 57344 57344 4096 300.07 6.96 3.52 2.16 41.461 101.728
> I am a bit concerned about the throughput over half duplex 10Mbps connection.
> Could some body tell how throughput can go low at 10Mbps?
Collisions of the data with the acks. The TCP ack clock gets out of sync.
> Simon Andrew Boggi got similar result over a half duplex connection
> with eepro100.
> With 21143 based card we get the throughput around
> 9.2 on 10Mbps. I do not know if there is any problem with 82559 in half duplex mode.
The 21143 uses a special patented Ethernet collision backoff algorithm that
works better than the normal backoff. The 82559 probably doesn't.
Morale: half duplex hurts.
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This archive was generated by hypermail 2b29 : Wed May 31 2000 - 21:00:28 EST