Actually the size is suppose to be the same, It just suppose to bind process to it's closer memory node, instead of leaving it to OS.
see: mpool_sm_module.c:82: opal_maffinity_base_bind(&mseg, 1, mpool_sm->mem_node); Best regards Lenny. On Mon, Jan 12, 2009 at 10:02 PM, Eugene Loh <eugene....@sun.com> wrote: > I'm trying to understand how much shared memory is allocated when maffinity > is on. > > The sm BTL sets up a file that is mmapped into each local process's address > space so that the processes on a node can communicate via shared memory. > > Actually, when maffinity indicates that there are multiple "memory nodes" on > the node, then a separate file is set up and mmapped for each "memory node". > > There is an MCA parameter named "[mpool_sm_per_]peer_size", which by default > is 32 Mbytes. The idea is that there are n processes on the node, then the > size of the file to be mmapped in is n*32M. > > But, if there are multiple "memory nodes", will there be that much more > shared memory? That is, is the total amount of shared memory that's mmapped > into all the processes: > > mem_nodes * num_local_procs * peer_size > > Or, should the file for a memory node be created with size proportional to > the number of processes that correspond to that memory node? > _______________________________________________ > devel mailing list > de...@open-mpi.org > http://www.open-mpi.org/mailman/listinfo.cgi/devel >
