On Apr 30, 2011, at 11:09 AM, Cosimo Calabrese <cosimo.calabrese@tellus.it> wrote:
Hi to all,
I'm working on WinXP, VS2010, boost 1.46.1. I've writed this short program:
//---------------------------------- #include <boost/graph/use_mpi.hpp> #include <boost/graph/distributed/mpi_process_group.hpp> #include <boost/graph/distributed/adjacency_list.hpp>
using boost::graph::distributed::mpi_process_group;
typedef boost::property<boost::vertex_distance_t, long, boost::property<boost::vertex_name_t, std::string > > vertex_prop; typedef boost::property<boost::edge_weight_t, long > edge_prop; typedef boost::adjacency_list< boost::vecS, boost::distributedS<mpi_process_group, boost::vecS>, boost::directedS, vertex_prop, edge_prop > Graph; typedef boost::graph_traits<Graph>::edge_descriptor EdgeDescriptor; typedef boost::graph_traits<Graph>::vertex_descriptor VertexDescriptor;
int main(int argc, char* argv[]) { boost::mpi::environment env(argc,argv); Graph g( 10 ); return 0; } //----------------------------------
When I launch it, every process allocates about 1 GB of memory. Why it allocates all that memory? Is it normal? Is there any tuning to the PBGL framework that I must made?
I use it on a 2-core machine, and the command that I use is:
mpiexec -n 2 .\test.exe
I've tried with openMPI 1.4.3 and Microsoft HPC Pack 2008, but it seems irrilevant.
A large portion of this is likely due to the comm buffers in the mpi_process_group. Buffers which aren't used are never read so it shouldn't be a performance issue if your system has virtual memory. The number of buffers is set using a define in mpi_process_group.hpp, the size of each buffer is set in the ctor. Let me know if you need more details (I kept this explanation brief as I'm writing it on my iPhone) -Nick