opensand team mailing list archive

[Julien BERNARD <jbernard@xxxxxxxxxxxxxxxxxxx>]

Hi Andrei,
> Yes, that's right. I use the same configuration and send traffic from 
> WS behind the GW to WS behind the ST. And I don't run opensnad-network 
> and opensand-daemon services on both workstations. I found that 
> WS-daemon adds route to the network behind ST or GW. I use static 
> routing instead. Please let me know if it's essential to run WS-daemon 
> services and if they have another functions besides routing.

You don't need to use the OpenSAND daemon on the workstation.
They can be useful for our automatic tests or for tools deployments but 
it isn't your case.

> As I said in previous letters, all machines are virtual machines 
> hosted on one single machine. And may be I should add that I use 1.0 
> version of OpenSand. The problem itself is random but in my case it 
> can be reproduced on the second-forth experimental try after starting 
> OpenSand. In fact, this problem appeared only when I started testing 
> GW-to-ST direction. In ST-to-GW direction TCP worked fine with BE 
> buffers in the range from 3000 to 30 000. With buffer less than 3000 
> TCP performance decreases and with very low buffers (don't remember 
> exactly - may be 50-100) iperf refused to establish connection and 
> send traffic.

I assumed you were on version 2.0.0 so my tests are not relevant.
Do you plan to install the 2.0.0 version ? It may solve your problems, 
as I said I got some crashes but not so often.

For the TCP performances, they are bad with small buffers because the 
size is in number of packets and the ATM cells or MPEG packets are small 
compared to your IP packets. So, your queues are full after receiving a 
small amount of IP packets and you lost packets quickly.

For very small buffer it is strange because iperf sends small packets 
at  beginning and with a buffer size of 50-100 even with large packets 
you should be able to transmit some packets. Does OpenSAND reports 
errors in this case ?


Best regards,

--
Julien BERNARD