Hello
I'm sending occasional large bursts of UDP traffic from the MOD5234 that are overflowing transmit and receive buffers and losing messages. Which parameters can I tweak to increase the amount of storage to handle these bursts. Do I increase the size or number of fifos or is there another way?
At the moment I've added some application layer handshaking to compensate but its slowing down the system and I'd like to avoid if possible.
Thanks in advance
Kevin
UDP buffers
Re: UDP buffers
The amount of UDP packets you can receive or send is limited by the total size of the buffer pool. The number of fifos, default at 10, will only limit the number of UDP ports you can have open at a single time. It sounds like you are sending and receiving data from only 1 or 2 ports so the default fifo limit should be fine.
You can try increasing your buffer pool by increasing the "BUFFER_POOL_SIZE" define in C:\Nburn\include\constants.h. You should also make sure that you are using NNDK 2.2rc2 as the UDP transmit and receive speeds have increased about 300% from older builds.
If you are not actively reading from the UDP fifo your buffers will overflow rather quickly and packets will be thrown away. Also if you block level 1 interrupts for longer then the time it takes to receive 10 packets then you will lose packets. You should probably be using TCP instead of UDP for any data that MUST be successfully transmitted across the network.
You can try increasing your buffer pool by increasing the "BUFFER_POOL_SIZE" define in C:\Nburn\include\constants.h. You should also make sure that you are using NNDK 2.2rc2 as the UDP transmit and receive speeds have increased about 300% from older builds.
If you are not actively reading from the UDP fifo your buffers will overflow rather quickly and packets will be thrown away. Also if you block level 1 interrupts for longer then the time it takes to receive 10 packets then you will lose packets. You should probably be using TCP instead of UDP for any data that MUST be successfully transmitted across the network.
Re: UDP buffers
Thanks for the quick response.
Yes we're sending and receiving over just two ports. I saw the note about NNDK 2.2rc2 but I haven't tried it yet. I'll try to install it later today. The UDP read task is quite high priority but I'll check for blocking of level one interrupt as you suggest.
Sadly I'm stuck with UDP for a while as the OSC protocol we're using is optimized for that. The problem only occurs on periodic dumping of status data back to the controller on connect, but the handshaking needed to guarantee receipt of that data can't be turned on and off for just that instance.
Kevin
Yes we're sending and receiving over just two ports. I saw the note about NNDK 2.2rc2 but I haven't tried it yet. I'll try to install it later today. The UDP read task is quite high priority but I'll check for blocking of level one interrupt as you suggest.
Sadly I'm stuck with UDP for a while as the OSC protocol we're using is optimized for that. The problem only occurs on periodic dumping of status data back to the controller on connect, but the handshaking needed to guarantee receipt of that data can't be turned on and off for just that instance.
Kevin