Hi! I'm using OpenMPI 1.3 on two nodes connected with Infiniband; i'm using Gentoo Linux x86_64.
I've noticed that before any application starts there is a variable amount of time (around 3.5 seconds) in which the terminal just hangs with no output and then the application starts and works well. I imagined that there might have been some initialization routine somewhere in the Infiniband layer or in the software stack, but as i continued my tests i observed that this "latency" time is not present in other MPI implementations (like mvapich2) where my application starts immediately (but performs worse). Is my MPI configuration/installation broken or is this expected behaviour? thanks a lot! Vittorio