[Top][All Lists]

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Discuss-gnuradio] Why am I dropping data over the UDP network?

From: Ward, Marcus D.
Subject: Re: [Discuss-gnuradio] Why am I dropping data over the UDP network?
Date: Mon, 14 Jul 2014 16:07:38 -0400

I forgot to add that the 1e6 data rate was going to a null sink.

The data rate is only 1Mhz * 4bytes * 2 channels = 8M bytes per second to a 
null sink, which should be fine. Does anyone have any suggestions as to what  
settings I should have in my UDP source block in terms of payload size, buffer 
size, etc.?


-----Original Message-----
From: Ward, Marcus D. 
Sent: Monday, July 14, 2014 4:02 PM
To: address@hidden
Subject: RE: [Discuss-gnuradio] Why am I dropping data over the UDP network?

The UDP sink doesn't support complex int 16, so what would I be able to change 
the type to in order to come to a close solution for this problem? 

Also, I have lowered the sample rate to very small amounts such as 1e6, but I 
still lose packages on the receiving end. There is a 1-gigabit switch between 
the two USRP's, so it is a very simple network. I don't think the network is 
the problem.

-----Original Message-----
From: address@hidden [mailto:address@hidden On Behalf Of Marcus Müller
Sent: Friday, July 11, 2014 8:59 PM
To: address@hidden
Subject: Re: [Discuss-gnuradio] Why am I dropping data over the UDP network?

No, building vectors out of streams would (in the best case) change nothing, as 
you don't send individual samples but always packets full of payloads.

Also, if you have a hardware device defining your data rate, you will never 
need a throttle, and having one will most likely only introduce problems, so 
remove it from your flowgraph. All throttle really does is trying to achieve a 
given *average* sample processing rate, and that interferes with the hardware 
*constantly* providing a sample rate.

A few numbers in my head: 500ksps = 500 * 32kbps = 16000kbps, not very much for 
a gigabit ethernet! So I think it's safe to assume that the physical network is 
not to blame here, and usually the CPU load, maybe introduced by network 
handling might be to blame, if this doesn't happen with a null sink.


On 11.07.2014 19:49, madengr wrote:
> Funny that I was doing the exact same thing last night, and I'm also 
> getting warnings on the receive end at only 500 ksps on a home LAN.
> Should the stream be vectorized before the UDP sink, and if so how 
> long?  I tried both stream and vectors but still get the warnings.
> Lou
> Ward, Marcus D. wrote
>> Hey Everyone,
>> I am sending a signal from one USRP to another USRP through a UDP network.
>> It seems to work but I am getting data loss as gnu-radio runs the 
>> flow graph. Hopefully someone could help me with this problem?
>> P.S. I have the sender side (RecieveStation.jpg) and the 
>> Reciever/Display side (RecieveDisplay.jpg) attached
> --
> View this message in context: 
> http://gnuradio.4.n7.nabble.com/Why-am-I-dropping-data-over-the-UDP-ne
> twork-tp49283p49286.html Sent from the GnuRadio mailing list archive 
> at Nabble.com.
> _______________________________________________
> Discuss-gnuradio mailing list
> address@hidden
> https://lists.gnu.org/mailman/listinfo/discuss-gnuradio

Discuss-gnuradio mailing list

reply via email to

[Prev in Thread] Current Thread [Next in Thread]