Change the ORTE datatype service in 2 ways:

1. Remove a unneeded field, bytes_avail, from orte_buffer_t. It is a calcualed value, and updating it everywhere is worse then just calculating it in the one place it is acutally used.
2. Change it so the default size of a orte_buffer is 128 bytes instead of 1024 bytes. We then double the size of the buffer up to 1024 bytes, then we additively increase the size by 1024 bytes at a time as was done before.

This commit was SVN r14252.

orte/dss/dss_internal.h

@@ -39,10 +39,14 @@ extern "C" {
 #endif
 
 /*
- * DEFINE THE DEFAULT PAGE SIZE FOR THE DSS BUFFERS - IN KILOBYTES
+ * The default starting chunk size
  */
-#define ORTE_DSS_DEFAULT_PAGE_SIZE  1
-
+#define ORTE_DSS_DEFAULT_INITIAL_SIZE  128
+/*
+ * The default threshold size when we switch from doubling the 
+ * buffer size to addatively increasing it
+ */
+#define ORTE_DSS_DEFAULT_THRESHOLD_SIZE 1024
 
 /*
  * Internal type corresponding to size_t.  Do not use this in
@@ -199,7 +203,8 @@ ORTE_DECLSPEC OBJ_CLASS_DECLARATION(orte_dss_type_info_t);
 extern bool orte_dss_initialized;
 extern bool orte_dss_debug;
 extern int orte_dss_verbose;
-extern int orte_dss_page_size;
+extern int orte_dss_initial_size;
+extern int orte_dss_threshold_size;
 extern orte_pointer_array_t *orte_dss_types;
 extern orte_data_type_t orte_dss_num_reg_types;
 

orte/dss/dss_internal_functions.c

@@ -39,34 +39,39 @@
  */
 char* orte_dss_buffer_extend(orte_buffer_t *buffer, size_t bytes_to_add)
 {
-    size_t required, num_pages;
+    size_t required, to_alloc;
     size_t pack_offset, unpack_offset;
 
     /* Check to see if we have enough space already */
 
-    if (buffer->bytes_avail >= bytes_to_add) {
+    if ((buffer->bytes_allocated - buffer->bytes_used) >= bytes_to_add) {
         return buffer->pack_ptr;
     }
 
-    /* If we don't, see how many pages will be required and alloc
-       that */
-
     required = buffer->bytes_used + bytes_to_add;
-    num_pages = required / orte_dss_page_size;
-    if (0 != required % orte_dss_page_size) {
-        ++num_pages;
+    if(required >= (size_t)orte_dss_threshold_size) {
+        to_alloc = ((required + orte_dss_threshold_size - 1) 
+                    / orte_dss_threshold_size) * orte_dss_threshold_size;
+    } else {
+        to_alloc = buffer->bytes_allocated;
+        if(0 == to_alloc) {
+            to_alloc = orte_dss_initial_size;
+        }
+        while(to_alloc < required) {
+            to_alloc <<= 1;
+        } 
     }
+
     if (NULL != buffer->base_ptr) {
         pack_offset = ((char*) buffer->pack_ptr) - ((char*) buffer->base_ptr);
         unpack_offset = ((char*) buffer->unpack_ptr) -
             ((char*) buffer->base_ptr);
-        buffer->base_ptr = (char*)realloc(buffer->base_ptr, 
-                                          num_pages * orte_dss_page_size);
+        buffer->base_ptr = (char*)realloc(buffer->base_ptr, to_alloc);
     } else {
         pack_offset = 0;
         unpack_offset = 0;
         buffer->bytes_used = 0;
-        buffer->base_ptr = (char*)malloc(num_pages * orte_dss_page_size);
+        buffer->base_ptr = (char*)malloc(to_alloc);
     }
     
     if (NULL == buffer->base_ptr) { 
@@ -75,8 +80,7 @@ char* orte_dss_buffer_extend(orte_buffer_t *buffer, size_t bytes_to_add)
     }
     buffer->pack_ptr = ((char*) buffer->base_ptr) + pack_offset;
     buffer->unpack_ptr = ((char*) buffer->base_ptr) + unpack_offset;
-    buffer->bytes_allocated = num_pages * orte_dss_page_size;
-    buffer->bytes_avail = buffer->bytes_allocated - buffer->bytes_used;
+    buffer->bytes_allocated = to_alloc;
     
     /* All done */
 

orte/dss/dss_load_unload.c

@@ -78,7 +78,7 @@ int orte_dss_unload(orte_buffer_t *buffer, void **payload,
     /* dereference everything in buffer */
     buffer->base_ptr = NULL;
     buffer->pack_ptr = buffer->unpack_ptr = NULL;
-    buffer->bytes_allocated = buffer->bytes_used = buffer->bytes_avail = 0;
+    buffer->bytes_allocated = buffer->bytes_used = 0;
 
     /* All done */
 
@@ -123,7 +123,6 @@ int orte_dss_load(orte_buffer_t *buffer, void *payload,
 
     /* set counts for size and space */
     buffer->bytes_allocated = buffer->bytes_used = bytes_used;
-    buffer->bytes_avail = 0;
 
     /* All done */
 

orte/dss/dss_open_close.c

@@ -34,7 +34,8 @@
 bool orte_dss_initialized = false;
 bool orte_dss_debug = false;
 int orte_dss_verbose = -1;  /* by default disabled */
-int orte_dss_page_size;
+int orte_dss_initial_size;
+int orte_dss_threshold_size;
 orte_pointer_array_t *orte_dss_types;
 orte_data_type_t orte_dss_num_reg_types;
 orte_dss_buffer_type_t default_buf_type;
@@ -96,7 +97,7 @@ static void orte_buffer_construct (orte_buffer_t* buffer)
     /* Make everything NULL to begin with */
 
     buffer->base_ptr = buffer->pack_ptr = buffer->unpack_ptr = NULL;
-    buffer->bytes_allocated = buffer->bytes_used = buffer->bytes_avail = 0;
+    buffer->bytes_allocated = buffer->bytes_used = 0;
 }
 
 static void orte_buffer_destruct (orte_buffer_t* buffer)
@@ -142,7 +143,7 @@ OBJ_CLASS_INSTANCE(orte_dss_type_info_t, opal_object_t,
 int orte_dss_open(void)
 {
     char *enviro_val;
-    int id, page_size, rc;
+    int id, rc;
     orte_data_type_t tmp;
     int def_type;
 
@@ -173,13 +174,16 @@ int orte_dss_open(void)
     mca_base_param_lookup_int(id, &rc);
     default_buf_type = rc;
 
-    /* setup the page size -this is for use by the BUFFER system, NOT the data type
-       manager that keeps track of registered data types!! It must be converted to
-       bytes since the buffer system will allocate a "page_size" at a time.
-    */
-    id = mca_base_param_register_int("dss", "page", "size", NULL, ORTE_DSS_DEFAULT_PAGE_SIZE);
-    mca_base_param_lookup_int(id, &page_size);
-    orte_dss_page_size = 1024*page_size;
+    /* setup the initial size of the buffer. */
+    id = mca_base_param_register_int("dss", "buffer_initial", "size", NULL, 
+                                     ORTE_DSS_DEFAULT_INITIAL_SIZE);
+    mca_base_param_lookup_int(id, &orte_dss_initial_size);
+
+    /* the threshold as to where to stop doubling the size of the buffer 
+     * allocated memory and start doing additive increases */
+    id = mca_base_param_register_int("dss", "buffer_threshold", "size", NULL, 
+                                     ORTE_DSS_DEFAULT_THRESHOLD_SIZE);
+    mca_base_param_lookup_int(id, &orte_dss_threshold_size);
 
     /* Setup the types array */
 

orte/dss/dss_pack.c

@@ -228,8 +228,6 @@ int orte_dss_pack_null(orte_buffer_t *buffer, void *src,
     /* update buffer pointers */
     buffer->pack_ptr += num_vals;
     buffer->bytes_used += num_vals;
-    buffer->bytes_avail -= num_vals;
-
 
     return ORTE_SUCCESS;
 }
@@ -255,7 +253,6 @@ int orte_dss_pack_byte(orte_buffer_t *buffer, void *src,
     /* update buffer pointers */
     buffer->pack_ptr += num_vals;
     buffer->bytes_used += num_vals;
-    buffer->bytes_avail -= num_vals;
 
     return ORTE_SUCCESS;
 }
@@ -284,7 +281,6 @@ int orte_dss_pack_int16(orte_buffer_t *buffer, void *src,
     }
     buffer->pack_ptr += num_vals * sizeof(tmp);
     buffer->bytes_used += num_vals * sizeof(tmp);
-    buffer->bytes_avail -= num_vals * sizeof(tmp);
 
     return ORTE_SUCCESS;
 }
@@ -313,7 +309,6 @@ int orte_dss_pack_int32(orte_buffer_t *buffer, void *src,
     }
     buffer->pack_ptr += num_vals * sizeof(tmp);
     buffer->bytes_used += num_vals * sizeof(tmp);
-    buffer->bytes_avail -= num_vals * sizeof(tmp);
 
     return ORTE_SUCCESS;
 }
@@ -343,7 +338,6 @@ int orte_dss_pack_int64(orte_buffer_t *buffer, void *src,
     }
     buffer->pack_ptr += bytes_packed;
     buffer->bytes_used += bytes_packed;
-    buffer->bytes_avail -= bytes_packed;
 
     return ORTE_SUCCESS;
 }

orte/dss/dss_types.h

@@ -93,10 +93,6 @@ typedef uint8_t orte_dss_buffer_type_t;
         /** Number of bytes used by the buffer (i.e., amount of data --
             including overhead -- packed in the buffer) */
         size_t bytes_used;
-        /** How many bytes are available in the allocated buffer -- kept
-            here for convenience rather than recalculating it all the
-            time */
-        size_t bytes_avail;
     };
     /**
      * Convenience typedef