slow Kilauea TCP throughput?

slow Kilauea TCP throughput?

[Donasch, Ingo @ SDS]

I have a project where I would like to use the AMC405EX under Linux for
high speed data acquisition. I have the Kilauea board in the lab but
measured only 150Mbit/s TCP throughput (outbound) with iperf. I need
twice of that and actually expecting 3x higher bandwidth from that
architecture.
what is it that I'm missing?
can anybody confirm my results or tell me what am I doing wrong?
any help is appreciated
sincerely
ingo

/home # uname -a
Linux kilauea 2.6.23-g1dfaad37 #1 Wed Nov 21 07:15:18 CET 2007 ppc
unknown

home # ./iperf -c 192.168.1.249 -t60 -i1
------------------------------------------------------------
Client connecting to 192.168.1.249, TCP port 5001 TCP window size: 16.0
KByte (default)
------------------------------------------------------------
[  5] local 192.168.1.50 port 59035 connected with 192.168.1.249 port
5001
[  5]  0.0- 1.0 sec  16.6 MBytes    139 Mbits/sec
[  5]  1.0- 2.0 sec  16.6 MBytes    140 Mbits/sec
...
[  5] 58.0-59.0 sec  18.0 MBytes    151 Mbits/sec
[  5] 59.0-60.0 sec  18.0 MBytes    151 Mbits/sec
[  5]  0.0-60.0 sec  1.04 GBytes    148 Mbits/sec
/home # ifconfig
eth0      Link encap:Ethernet  HWaddr 00:06:4B:10:19:5B =20
          inet addr:192.168.1.50  Bcast:192.168.1.255
Mask:255.255.255.0
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:798928 errors:0 dropped:0 overruns:0 frame:0
          TX packets:1634765 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000=20
          RX bytes:53947650 (51.4 MiB)  TX bytes:2341215308 (2.1 GiB)

lo        Link encap:Local Loopback =20
          inet addr:127.0.0.1  Mask:255.0.0.0
          UP LOOPBACK RUNNING  MTU:16436  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0=20
          RX bytes:0 (0.0 B)  TX bytes:0 (0.0 B)


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Re: slow Kilauea TCP throughput?

[Stefan Roese]

On Wednesday 12 March 2008, Donasch, Ingo @ SDS wrote:
> I have a project where I would like to use the AMC405EX under Linux for
> high speed data acquisition. I have the Kilauea board in the lab but
> measured only 150Mbit/s TCP throughput (outbound) with iperf. I need
> twice of that and actually expecting 3x higher bandwidth from that
> architecture.

I'm not sure if 3 times the performace will be possible. Why did you expect 
such a performance btw?

> what is it that I'm missing?
> can anybody confirm my results or tell me what am I doing wrong?

I just ran some iperf tests and they show similar results. I'll currently 
comparing them to other 4xx platforms. Perhaps this gives some infos on what 
is happening here and where the bottleneck lies.

Best regards,
Stefan

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