diff --git a/config.h.in b/config.h.in
index 041c9cb..558ea81 100644
--- a/config.h.in
+++ b/config.h.in
@@ -1,32 +1,5 @@
 /* config.h.in.  Generated from configure.ac by autoheader.  */
 
-/* Define to 1 if you have the <inttypes.h> header file. */
-#undef HAVE_INTTYPES_H
-
-/* Define to 1 if you have the <memory.h> header file. */
-#undef HAVE_MEMORY_H
-
-/* Define to 1 if you have the <stdint.h> header file. */
-#undef HAVE_STDINT_H
-
-/* Define to 1 if you have the <stdlib.h> header file. */
-#undef HAVE_STDLIB_H
-
-/* Define to 1 if you have the <strings.h> header file. */
-#undef HAVE_STRINGS_H
-
-/* Define to 1 if you have the <string.h> header file. */
-#undef HAVE_STRING_H
-
-/* Define to 1 if you have the <sys/stat.h> header file. */
-#undef HAVE_SYS_STAT_H
-
-/* Define to 1 if you have the <sys/types.h> header file. */
-#undef HAVE_SYS_TYPES_H
-
-/* Define to 1 if you have the <unistd.h> header file. */
-#undef HAVE_UNISTD_H
-
 /* "" */
 #undef MY_BUILD_CPU
 
@@ -60,40 +33,12 @@
 /* Define to the version of this package. */
 #undef PACKAGE_VERSION
 
-/* Define to 1 if you have the ANSI C header files. */
-#undef STDC_HEADERS
-
-/* Enable extensions on AIX 3, Interix.  */
-#ifndef _ALL_SOURCE
-# undef _ALL_SOURCE
-#endif
-/* Enable GNU extensions on systems that have them.  */
-#ifndef _GNU_SOURCE
-# undef _GNU_SOURCE
-#endif
-/* Enable threading extensions on Solaris.  */
-#ifndef _POSIX_PTHREAD_SEMANTICS
-# undef _POSIX_PTHREAD_SEMANTICS
-#endif
-/* Enable extensions on HP NonStop.  */
-#ifndef _TANDEM_SOURCE
-# undef _TANDEM_SOURCE
-#endif
-/* Enable general extensions on Solaris.  */
-#ifndef __EXTENSIONS__
-# undef __EXTENSIONS__
-#endif
-
-
 /* Version number of package */
 #undef VERSION
 
-/* Define to 1 if on MINIX. */
-#undef _MINIX
-
-/* Define to 2 if the system does not provide POSIX.1 features except with
-   this defined. */
-#undef _POSIX_1_SOURCE
-
-/* Define to 1 if you need to in order for `stat' and other things to work. */
-#undef _POSIX_SOURCE
+/* Define to 1 if on AIX 3.
+   System headers sometimes define this.
+   We just want to avoid a redefinition error message.  */
+#ifndef _ALL_SOURCE
+# undef _ALL_SOURCE
+#endif
diff --git a/src/H5Part.c b/src/H5Part.c
index ed71d68..0ecb0f3 100644
--- a/src/H5Part.c
+++ b/src/H5Part.c
@@ -227,30 +227,33 @@ _H5Part_open_file (
 		if ( flags & H5PART_FS_LUSTRE )
 		{
 			/* extend the btree size so that metadata pieces are
-			 * close to the alignment value */
-			unsigned int btree_ik = (align - 256) / 96;
-			unsigned int btree_bytes = 64 + 96*btree_ik;
-			if ( btree_bytes > align ) {
-				HANDLE_H5PART_INVALID_ERR(
-					"btree_ik", btree_ik );
-				goto error_cleanup;
+		 	* close to the alignment value */
+			if ( align > 0 )
+			{
+				unsigned int btree_ik = (align - 4096) / 96;
+				unsigned int btree_bytes = 64 + 96*btree_ik;
+				if ( btree_bytes > align ) {
+					HANDLE_H5PART_INVALID_ERR(
+						"btree_ik", btree_ik );
+					goto error_cleanup;
+				}
+
+				_H5Part_print_info (
+					"Setting HDF5 btree parameter to %u",
+					btree_ik );
+				_H5Part_print_info (
+					"Extending HDF5 btree size to %u "
+					"bytes at rank 3", btree_bytes );
+
+				f->fcreate_prop = H5Pcreate(H5P_FILE_CREATE);
+				if ( f->fcreate_prop < 0 ) {
+					HANDLE_H5P_CREATE_ERR;
+					goto error_cleanup;
+				}
+
+				H5Pset_istore_k (f->fcreate_prop, btree_ik);
 			}
 
-			_H5Part_print_info (
-				"Setting HDF5 btree parameter to %u",
-				btree_ik );
-			_H5Part_print_info (
-				"Extending HDF5 btree size to %u bytes at rank 3",
-				btree_bytes );
-
-			f->fcreate_prop = H5Pcreate(H5P_FILE_CREATE);
-			if ( f->fcreate_prop < 0 ) {
-				HANDLE_H5P_CREATE_ERR;
-				goto error_cleanup;
-			}
-
-			H5Pset_istore_k (f->fcreate_prop, btree_ik);
-
 #ifdef H5PART_HAVE_HDF5_18
 			/* defer metadata cache flushing until file close */
 			H5AC_cache_config_t cache_config;
@@ -269,6 +272,36 @@ _H5Part_open_file (
 #endif // H5_USE_16_API
 		}
 
+		/* select the HDF5 VFD */
+		if (flags & H5PART_VFD_MPIPOSIX) {
+			_H5Part_print_info ( "Selecting MPI-POSIX VFD" );
+			if (H5Pset_fapl_mpiposix ( f->access_prop, comm, 0 ) < 0) {
+				HANDLE_H5P_SET_FAPL_ERR;
+				goto error_cleanup;
+			}
+		}
+		else {
+			_H5Part_print_info ( "Selecting MPI-IO VFD" );
+			if (H5Pset_fapl_mpio ( f->access_prop, comm, info ) < 0) {
+				HANDLE_H5P_SET_FAPL_ERR;
+				goto error_cleanup;
+			}
+			if (flags & H5PART_VFD_MPIIO_IND) {
+				_H5Part_print_info ( "Using independent mode" );
+			} else {
+				_H5Part_print_info ( "Using collective mode" );
+				f->xfer_prop = H5Pcreate (H5P_DATASET_XFER);
+				if (f->xfer_prop < 0) {
+					HANDLE_H5P_CREATE_ERR;
+					goto error_cleanup;
+				}
+				if (H5Pset_dxpl_mpio ( f->xfer_prop, H5FD_MPIO_COLLECTIVE ) < 0) {
+					HANDLE_H5P_SET_DXPL_MPIO_ERR;
+					goto error_cleanup;
+				}
+			}
+		}
+
 		f->comm = comm;
 #endif // PARALLEL_IO
 	} else {