I am reading UDP datagrams on a linux server at 700,000 per second from HDL32 LIDAR system. Interface is ipv4. Sockets are set to SOREUSADDR. I turn on the LIDAR, start up socket program, it started reading datagrams. It ran for about 4 hours then I turned off program reading while LIDAR was still operating.
LIDAR is turned off. I run program it's reading old packets. Turn Linux off, restart, it's still reading packets. Service network restart; still reading old packets.
It's impressive to say the least but...
Question 1; how do I tell Linux to clear old UDP datagrams ? Use sysctl? Do I clear ipv4.udp_mem?
Question 2. In the future, what startup routine should I adopt to make sure old data is off the stack?