UDP Causes Freezing

Has anyone run into this problem? Experiencing a lot of freezing in two different scenarios…

1st scenario – sending large packets with OSC (every 5 seconds) to a different host

get a freeze almost every time it sends packets

2nd scenario – I start two instances (vvvv.exe and vvvv2.exe) and use SetProcessAffinityMask to run vvvv2.exe with a different cpu core. vvvv2 patch uses FreeFrame plugin ColorTracker. vvvv2 patch sends data continuously via UDP to vvvv patch.

extreme slugishness

heard you can use S/R nodes for that

ai gilbi,

probably udp is not the right protocol for this task. you mention “sending large packets”. what is large here?

for my understanding it depends on the underlying hardware how large you can go with packets. note that the UDP (Network Server) has a Buffer Size which defaults to 8192bytes. so it won’t be able to receive larger packets by default (even your network hardware supported that). iirc i read somewhere that those 8k are a typical limit so it won’t typically work with more than that anyway.

probably SharedMemory (Windows) is more useful at least when communicating between two instances on the same PC.

anyway make sure to reduce the data sent between the instances to a minimum necessary.

@antokhio: S/R nodes only work within one vvvv instance.

thanks, good to know, that it’s shared mem, looks like gonna need 2-d instance soon…

re: 1st Scenario – I’m sending 992 characters. I could split this up into smaller packets, but I’d still like to know why this is happening. Of all the operations in my patch I did not expect this to be the heavy one.

re: 2nd Scenario – Thanks for clearing that up, I’ll look into using SharedMemory.

so 992 times 8byte makes 7936byte you are trying to send in one packet, which is probably a problem (as mentioned above). try to split that up in packets <1472bytes (which seems to be a magic UDP number) and see if that makes a difference.

anyway avoid using IOBox (String) with large packets.
it tries to render all the characters contained in the string.