[svn-r6387] Purpose:

    Bug Fix

Description:
    Metadata cache in parallel I/O can cause hangs in applications which
    perform independent I/O on chunked datasets, because the metadata cache
    can attempt to flush out dirty metadata from only a single process, instead
    of collectively from all processes.

Solution:
    Pass a dataset transfer property list down from every API function which
    could possibly trigger metadata I/O.

    Then, split the metadata cache into two sets of entries to allow dirty
    metadata to be set aside when a hash table collision occurs during
    independent I/O.

Platforms tested:
    Tested h5committest {arabica (fortran), eirene (fortran, C++)
        modi4 (parallel, fortran)}

    FreeBSD 4.7 (sleipnir) serial & parallel

Misc. update:
    Updated release_docs/RELEASE

1 files changed, 32 insertions, 48 deletions

diff --git a/src/H5Fseq.c b/src/H5Fseq.c
index 15cb668..fddf48f 100644
--- a/src/H5Fseq.c
+++ b/src/H5Fseq.c
@@ -176,7 +176,6 @@ H5F_seq_readv(H5F_t *f, hid_t dxpl_id, const H5O_layout_t *layout,
     int	i,j;				/*counters		*/
 #ifdef H5_HAVE_PARALLEL
     H5FD_mpio_xfer_t xfer_mode=H5FD_MPIO_INDEPENDENT;
-    H5P_genplist_t *plist=NULL;                 /* Property list */
 #endif /* H5_HAVE_PARALLEL */
     herr_t      ret_value = SUCCEED;            /* Return value */
    
@@ -191,32 +190,25 @@ H5F_seq_readv(H5F_t *f, hid_t dxpl_id, const H5O_layout_t *layout,
     assert(TRUE==H5P_isa_class(dxpl_id,H5P_DATASET_XFER));
 
 #ifdef H5_HAVE_PARALLEL
-    {
-	H5FD_mpio_dxpl_t *dx;
+    /* Get the transfer mode for MPIO transfers */
+    if(IS_H5FD_MPIO(f)) {
         hid_t driver_id;            /* VFL driver ID */
+        H5P_genplist_t *plist;      /* Property list */
 
-	/* Get the transfer mode for MPIO transfers */
-        if(IS_H5FD_MPIO(f)) {
-            /* Get the plist structure */
-            if(NULL == (plist = H5I_object(dxpl_id)))
-                HGOTO_ERROR(H5E_ATOM, H5E_BADATOM, FAIL, "can't find object for ID");
-
-            /* Get the driver ID */
-            if(H5P_get(plist, H5D_XFER_VFL_ID_NAME, &driver_id)<0)
-                HGOTO_ERROR (H5E_PLIST, H5E_CANTGET, FAIL, "Can't retrieve VFL driver ID");
-
-            /* Check if we are using the MPIO driver (for the DXPL) */
-            if(H5FD_MPIO==driver_id) {
-                /* Get the driver information */
-                if(H5P_get(plist, H5D_XFER_VFL_INFO_NAME, &dx)<0)
-                    HGOTO_ERROR (H5E_PLIST, H5E_CANTGET, FAIL, "Can't retrieve VFL driver info");
-
-                /* Check if we are not using independent I/O */
-                if(H5FD_MPIO_INDEPENDENT!=dx->xfer_mode)
-                    xfer_mode = dx->xfer_mode;
-            } /* end if */
+        /* Get the plist structure */
+        if(NULL == (plist = H5I_object(dxpl_id)))
+            HGOTO_ERROR(H5E_ATOM, H5E_BADATOM, FAIL, "can't find object for ID");
+
+        /* Get the driver ID */
+        if(H5P_get(plist, H5D_XFER_VFL_ID_NAME, &driver_id)<0)
+            HGOTO_ERROR (H5E_PLIST, H5E_CANTGET, FAIL, "Can't retrieve VFL driver ID");
+
+        /* Check if we are using the MPIO driver (for the DXPL) */
+        if(H5FD_MPIO==driver_id) {
+            /* Get the transfer mode */
+            xfer_mode=H5P_peek_unsigned(plist, H5D_XFER_IO_XFER_MODE_NAME);
         } /* end if */
-    }
+    } /* end if */
 
     /* Collective MPIO access is unsupported for non-contiguous datasets */
     if (H5D_CHUNKED==layout->type && H5FD_MPIO_COLLECTIVE==xfer_mode)
@@ -563,7 +555,6 @@ H5F_seq_writev(H5F_t *f, hid_t dxpl_id, H5O_layout_t *layout,
     int	i,j;				/*counters		*/
 #ifdef H5_HAVE_PARALLEL
     H5FD_mpio_xfer_t xfer_mode=H5FD_MPIO_INDEPENDENT;
-    H5P_genplist_t *plist=NULL;                 /* Property list */
 #endif /* H5_HAVE_PARALLEL */
     herr_t      ret_value = SUCCEED;            /* Return value */
    
@@ -578,32 +569,25 @@ H5F_seq_writev(H5F_t *f, hid_t dxpl_id, H5O_layout_t *layout,
     assert(TRUE==H5P_isa_class(dxpl_id,H5P_DATASET_XFER));
 
 #ifdef H5_HAVE_PARALLEL
-    {
-	H5FD_mpio_dxpl_t *dx;
+    /* Get the transfer mode for MPIO transfers */
+    if(IS_H5FD_MPIO(f)) {
         hid_t driver_id;            /* VFL driver ID */
+        H5P_genplist_t *plist=NULL;                 /* Property list */
+
+        /* Get the plist structure */
+        if(NULL == (plist = H5I_object(dxpl_id)))
+            HGOTO_ERROR(H5E_ATOM, H5E_BADATOM, FAIL, "can't find object for ID");
+
+        /* Get the driver ID */
+        if(H5P_get(plist, H5D_XFER_VFL_ID_NAME, &driver_id)<0)
+            HGOTO_ERROR (H5E_PLIST, H5E_CANTGET, FAIL, "Can't retrieve VFL driver ID");
 
-	/* Get the transfer mode for MPIO transfers */
-        if(IS_H5FD_MPIO(f)) {
-            /* Get the plist structure */
-            if(NULL == (plist = H5I_object(dxpl_id)))
-                HGOTO_ERROR(H5E_ATOM, H5E_BADATOM, FAIL, "can't find object for ID");
-
-            /* Get the driver ID */
-            if(H5P_get(plist, H5D_XFER_VFL_ID_NAME, &driver_id)<0)
-                HGOTO_ERROR (H5E_PLIST, H5E_CANTGET, FAIL, "Can't retrieve VFL driver ID");
-
-            /* Check if we are using the MPIO driver (for the DXPL) */
-            if(H5FD_MPIO==driver_id) {
-                /* Get the driver information */
-                if(H5P_get(plist, H5D_XFER_VFL_INFO_NAME, &dx)<0)
-                    HGOTO_ERROR (H5E_PLIST, H5E_CANTGET, FAIL, "Can't retrieve VFL driver info");
-
-                /* Check if we are not using independent I/O */
-                if(H5FD_MPIO_INDEPENDENT!=dx->xfer_mode)
-                    xfer_mode = dx->xfer_mode;
-            } /* end if */
+        /* Check if we are using the MPIO driver (for the DXPL) */
+        if(H5FD_MPIO==driver_id) {
+            /* Get the transfer mode */
+            xfer_mode=H5P_peek_unsigned(plist, H5D_XFER_IO_XFER_MODE_NAME);
         } /* end if */
-    }
+    } /* end if */
 
     /* Collective MPIO access is unsupported for non-contiguous datasets */
     if (H5D_CHUNKED==layout->type && H5FD_MPIO_COLLECTIVE==xfer_mode)