Open MPI's OpenFabrics support will spawn up to two additional blocking threads
(they wait for asynchronous verbs events of various flavors). They consume a
few resources, but typically are not used much. They don't cause any
noticeable change in performance.
On May 17, 2010, at 12:38 PM, Pi
Hello,
I found when running am MPI program that is linked against OpenMPI library,
for each MPI task, OpenMPI will spawn three threads, as the sample shown
below:
$ ps axms
...
13536 3565 ---
-pts/14 0:00 mpirun -n 2 ./a
