Add --oversubscribe to mpiexec command line if OpenMPI is used

Author: wkliao

darshan-runtime/configure.ac

@@ -918,6 +918,7 @@ AC_SUBST(HDF5_PATH, ["$with_hdf5"])
 AC_SUBST(PNETCDF_PATH, ["$with_pnetcdf"])
 AC_SUBST(DAOS_PATH, ["$with_daos"])
 AC_SUBST(LDMS_PATH, ["$LDMS_HOME"])
+AC_SUBST(HAVE_OPEN_MPI, ["$is_ompi"])
 
 AM_CONDITIONAL(ENABLE_MMAP_LOGS,    [test "x$enable_mmap_logs"   = xyes])
 AM_CONDITIONAL(ENABLE_LDPRELOAD,    [test "x$enable_ld_preload"  = xyes])

darshan-runtime/test/Makefile.am

@@ -17,6 +17,7 @@ AM_TESTS_ENVIRONMENT += export TST_DARSHAN_LOG_PATH="$(__DARSHAN_LOG_PATH)";
 AM_TESTS_ENVIRONMENT += export DARSHAN_INSTALL_DIR="$(prefix)";
 AM_TESTS_ENVIRONMENT += export USERNAME_ENV="$(USERNAME_ENV)";
 AM_TESTS_ENVIRONMENT += export HAVE_MPI_LARGE_COUNT="$(HAVE_MPI_LARGE_COUNT)";
+AM_TESTS_ENVIRONMENT += export HAVE_OPEN_MPI="$(HAVE_OPEN_MPI)";
 AM_TESTS_ENVIRONMENT += export check_PROGRAMS="$(check_PROGRAMS)";
 
 TESTS = tst_runs.sh

darshan-runtime/test/tst_runs.sh

@@ -34,12 +34,15 @@ echo "DARSHAN_CONFIG=$DARSHAN_CONFIG"
 
 $DARSHAN_CONFIG --all
 
-# run NP number of MPI processes
-# Note when using OpenMPI, setting NP > 2 will fail.
+# run NP number of MPI processes, default 2
 if test "x$NP" = x ; then
    NP=2
 fi
 
+if test "x$HAVE_OPEN_MPI" = x1 ; then
+   TESTMPIRUN="$TESTMPIRUN --oversubscribe"
+fi
+
 TEST_FILE=./testfile.dat
 
 # tst_mpi_io.c takes the following command-line options.