MDL-51498 core_grades: Prevent unnecessary grade record fetching

All of these changes make use of already fetched grade data. Without these changes, the gradebook regrade process does not scale well with very large courses because it fetches many grade records, one at a time.
robjoyce · Sep 22, 2015 · 5f6e2fc · 5f6e2fc
1 parent d230899
commit 5f6e2fc
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Showing 2 changed files with 7 additions and 4 deletions.
diff --git a/lib/grade/grade_category.php b/lib/grade/grade_category.php
@@ -466,7 +466,7 @@ public function generate_grades($userid=null) {
                      WHERE id $usql";
             $items = $DB->get_records_sql($sql, $params);
             foreach ($items as $id => $item) {
-                $items[$id] = new grade_item($item);
+                $items[$id] = new grade_item($item, false);
             }
         }
 
@@ -501,10 +501,13 @@ public function generate_grades($userid=null) {
             $grademinoverrides = array();
 
             foreach ($rs as $used) {
-                $grade = new grade_grade($used);
+                $grade = new grade_grade($used, false);
                 if (isset($items[$grade->itemid])) {
                     // Prevent grade item to be fetched from DB.
                     $grade->grade_item =& $items[$grade->itemid];
+                } else if ($grade->itemid == $this->grade_item->id) {
+                    // This grade's grade item is not in $items.
+                    $grade->grade_item =& $this->grade_item;
                 }
                 if ($grade->userid != $prevuser) {
                     $this->aggregate_grades($prevuser,
@@ -882,7 +885,7 @@ public function aggregate_values_and_adjust_bounds($grade_values,
                                                        & $weights = null,
                                                        $grademinoverrides = array(),
                                                        $grademaxoverrides = array()) {
-        $category_item = $this->get_grade_item();
+        $category_item = $this->load_grade_item();
         $grademin = $category_item->grademin;
         $grademax = $category_item->grademax;
 

diff --git a/lib/grade/grade_item.php b/lib/grade/grade_item.php
@@ -694,7 +694,7 @@ public function regrade_final_grades($userid=null) {
         // aggregate the category grade
         } else if ($this->is_category_item() or $this->is_course_item()) {
             // aggregate category grade item
-            $category = $this->get_item_category();
+            $category = $this->load_item_category();
             $category->grade_item =& $this;
             if ($category->generate_grades($userid)) {
                 return true;