[svn-r628] MPI buffer and file type optimization is bypassed,

unless the environment variable HDF5_MPI_OPT_TYPES is nonzero.

3 files changed, 24 insertions, 2 deletions

diff --git a/src/H5D.c b/src/H5D.c
index d9d0b78..c5550d7 100644
--- a/src/H5D.c
+++ b/src/H5D.c
@@ -1378,7 +1378,8 @@ H5D_read(H5D_t *dataset, const H5T_t *mem_type, const H5S_t *mem_space,
      * mem-and-file-dataspace-xfer functions
      * (the latter in case the arguments to sconv_funcs
      * turn out to be inappropriate for MPI-IO).  */
-    if (dataset->ent.file->shared->access_parms->driver == H5F_LOW_MPIO) {
+    if (H5_mpi_opt_types_g &&
+        H5F_LOW_MPIO==dataset->ent.file->shared->access_parms->driver) {
 	sconv->read = H5S_mpio_spaces_read;
     }
 #endif /*HAVE_PARALLEL*/
@@ -1730,7 +1731,8 @@ H5D_write(H5D_t *dataset, const H5T_t *mem_type, const H5S_t *mem_space,
      * mem-and-file-dataspace-xfer functions
      * (the latter in case the arguments to sconv_funcs
      * turn out to be inappropriate for MPI-IO).  */
-    if (dataset->ent.file->shared->access_parms->driver == H5F_LOW_MPIO) {
+    if (H5_mpi_opt_types_g &&
+        H5F_LOW_MPIO==dataset->ent.file->shared->access_parms->driver) {
 	sconv->write = H5S_mpio_spaces_write;
     }
 #endif /*HAVE_PARALLEL*/
diff --git a/src/H5S.c b/src/H5S.c
index 7ff39bb..a30f422 100644
--- a/src/H5S.c
+++ b/src/H5S.c
@@ -16,6 +16,7 @@ static char		RcsId[] = "@(#)$Revision$";
 
 /* $Id$ */
 
+#define _H5S_IN_H5S_C
 #include <H5private.h>		/* Generic Functions			  */
 #include <H5Iprivate.h>		/* ID Functions		  */
 #include <H5Eprivate.h>		/* Error handling		  */
@@ -39,6 +40,11 @@ static H5S_conv_t		**H5S_conv_g = NULL;
 static size_t			H5S_aconv_g = 0;	/*entries allocated*/
 static size_t			H5S_nconv_g = 0;	/*entries used*/
 
+#ifdef HAVE_PARALLEL
+/* Global var whose value comes from environment variable */
+hbool_t         H5_mpi_opt_types_g = FALSE;
+#endif
+
 
 /*--------------------------------------------------------------------------
 NAME
@@ -72,6 +78,14 @@ H5S_init_interface(void)
 		      "unable to register one or more conversion functions");
     }
     
+    {
+        /* Allow MPI buf-and-file-type optimizations? */
+        const char *s = getenv ("HDF5_MPI_OPT_TYPES");
+        if (s && isdigit(*s)) {
+            H5_mpi_opt_types_g = (int)HDstrtol (s, NULL, 0);
+        }
+    }
+
     FUNC_LEAVE(ret_value);
 }
 
diff --git a/src/H5Sprivate.h b/src/H5Sprivate.h
index 24dd4f6..fba178a 100644
--- a/src/H5Sprivate.h
+++ b/src/H5Sprivate.h
@@ -344,6 +344,12 @@ hbool_t H5S_hyper_select_valid (const H5S_t *space);
 		    const struct H5O_efl_t *efl, size_t elmt_size,
 		    const H5S_t *file_space, const H5S_t *mem_space,
 		    const H5D_transfer_t xfer_mode, const void *buf);
+
+#ifndef _H5S_IN_H5S_C
+    /* Global var whose value comes from environment variable */
+    extern hbool_t		H5_mpi_opt_types_g;
+#endif /* _H5S_IN_H5S_C */
+
 #endif
 
 #endif