Hi,
I'm using Open MPI in a real time rendering system and I need an accurate latency control.

consider the 'Nagle' optimization implemented in the TCP/IP protocol, which delays small packets for a short time period to possibly combine them with successive packets generating network friendly packet sizes.
This optimization can result in a better throughput when lots of small packets are sent, but can also lead to considerable latencies, if  packets get delayed several times.



For example, I want to turn the Nagle optimization on for sockets in which updated scene data is streamed to the clients, as throughput is the main issue here.
On the other hand, I want turn it off for e.g. sockets used to send tiles to the clients, as this has to be done with an absolute minimum of latency.

Can I do it with OpenMPI?
Am I using the the wrong tool?


Thanks in advance

Biagio Cosenza
an italian MSc student
Università di Salerno