TC65 : Slow UDP reception

Introduction Receiving UDP datagrams on the TC65 is easy but inefficient. You need to create a new thread if you want to receive data asynchronously. There’s no way of knowing if a new datagram has been received or not without hanging on the ::receive( Datagram ); method. This is quite weird considering you can do it in TCP. The real problem is it’s freaking slow. The Cinterion documentation just tells you “This method blocks until a datagram is received.”. What it doesn’t say is that nearly each time, it blocks for 100 to 700 ms after UDP datagrams have actually been received. And worse, this slowness/sleeping avoids the program from treating data and finally throws a little java.io.IOException exception : “No buffer space available”. I tried to give the udp receiving thread a higher priority than the other threads, I tried to make the TCP reception thread sleep a lot just in case it would lock some kind of network object, I looked on how could this method be implemented but couldn’t find a solution and don’t believe there’s one. ...

May 10, 2009 · Florent Clairambault