On Sun, Dec 16, 2007 at 06:49:30PM -0500, Allan Menezes wrote: > Hi, > How many PCI-Express Gigabit ethernet cards does OpenMPI version 1.2.4 > support with a corresponding linear increase in bandwith measured with > netpipe NPmpi and openmpi mpirun? > With two PCI express cards I get a B/W of 1.75Gbps for 892Mbps each ans > for three pci express cards ( one built into the motherboard) i get > 1.95Gbps. They all are around 890Mbs indiviually measured with netpipe > and NPtcp and NPmpi and openmpi. For two it seems there is a linear > increase in b/w but not for three pci express gigabit eth cards. > I have tune the cards using netpipe and $HOME/.openmpi/mca-params.conf > file for latency and percentage b/w . > Please advise. What is in your $HOME/.openmpi/mca-params.conf? May be are hitting your chipset limit here. What is your HW configuration? Can you try to run NPtcp on each interface simultaneously and see what BW do you get.
-- Gleb.