diff --git a/mod/forum/tests/generator_test.php b/mod/forum/tests/generator_test.php
index bf074b5..02b68d3 100644
--- a/mod/forum/tests/generator_test.php
+++ b/mod/forum/tests/generator_test.php
@@ -146,4 +146,74 @@ class mod_forum_generator_testcase extends advanced_testcase {
         $this->assertEquals(4, $DB->count_records_select('forum_posts', 'discussion = :discussion',
             array('discussion' => $discussion->id)));
     }
+    public function test_forumdataset() {
+        global $DB, $CFG;
+        require_once $CFG->dirroot.'/blocks/course_overview/locallib.php';
+        // use STDERR stream to get around buffering.
+        $this->resetAfterTest(true);
+        $run = 2;
+        $users = array();
+        $courses = array();
+        // Create a bunch of users
+        for ($i = 0; $i < $run; $i++) {
+            fwrite(STDERR, "Creating course $i" . PHP_EOL);
+            $users[] = self::getDataGenerator()->create_user();
+        }
+
+        // Create course to add the forum.
+        for ($i = 0; $i < $run; $i++) {
+            fwrite(STDERR, "Creating user $i" . PHP_EOL);
+            $record = new stdClass();
+            $record->groupmodeforce = false;
+            $record->groupmode = VISIBLEGROUPS;
+            $courses[] = self::getDataGenerator()->create_course($record);
+        }
+        foreach ($courses as $course) {
+            for ($i = 0; $i < $run; $i++) {
+                fwrite(STDERR, "Creating group $i in course with id $course->id" . PHP_EOL);
+                $record = new stdClass();
+                $record->courseid = $course->id;
+                $this->getDataGenerator()->create_group($record);
+            }
+        }
+        //die();
+        $users2 = $users;
+        $i = 0;
+        $role = $DB->get_record('role', array('shortname' => 'student'));
+
+        // Each user creates a forum in each course and than posts on everything.
+        foreach ($courses as $course) {
+            foreach ($users as $user) {
+                self::getDataGenerator()->enrol_user($user->id, $course->id, $role->id);
+                $record = new stdClass();
+                $record->course = $course->id;
+                $forum = self::getDataGenerator()->create_module('forum', $record, array("groupmode" => SEPARATEGROUPS));
+
+                // Add a discussion.
+                $record->forum = $forum->id;
+                $record->userid = $user->id;
+                $discussion = self::getDataGenerator()->get_plugin_generator('mod_forum')->create_discussion($record);
+                foreach ($users2 as $user) {
+                    $i++;
+                    fwrite(STDERR, "post number $i up" . PHP_EOL);
+                    // Add a bunch of replies, changing the userid.
+                    $record = new stdClass();
+                    $record->discussion = $discussion->id;
+                    $record->userid = $user->id;
+                    self::getDataGenerator()->get_plugin_generator('mod_forum')->create_post($record);
+                }
+            }
+        }
+
+        $html = array();
+        $this->setUser(array_shift($users));
+        list($sortedcourses, $xcourses, $totalcourses) = block_course_overview_get_sorted_courses();
+        $before = $DB->perf_get_queries();
+        forum_print_overview($xcourses, $html);
+        $after = $DB->perf_get_queries();
+        $count = $after - $before;
+        fwrite(STDERR, "DB calls before calling api : $before".PHP_EOL);
+        fwrite(STDERR, "DB calls after calling the api : $after".PHP_EOL);
+        fwrite(STDERR, "DB calls by the api : $count");
+    }
 }