I am sending very small packets (less than 100 bytes) over a TCP/IP link with a 10msecs round-trip delay. When I send several packets in a row (consecutive C-language socket writes), the first 2 or 3 get sent immediately (checked using the sniffer) but the remaining ones get delayed by another 10msecs (looks like the transmitter is waiting for an ACK from the receiver).
Nagle is turned off on both sides, I played with TCP_QUICKACK on the receiver with no luck; my RedHat Linux /proc/sys/net/ipv4/tcp_window_scaling == 1; have plenty of bandwiidth (100MBS).
What should I change/disable on TCP to be able to pump multiple packets at once? I want it real-time and dont care about bandwidth efficiencies (or UDP is the only way out ?)