Issue #2247095 by yched, xjm, alexpott: Optimize loading of deleted fields.

core/modules/field/src/FieldConfigStorage.php

@@ -97,7 +97,12 @@ public function loadByProperties(array $conditions = array()) {
     $include_deleted = isset($conditions['include_deleted']) ? $conditions['include_deleted'] : FALSE;
     unset($conditions['include_deleted']);
 
-    // Get fields stored in configuration.
+    $fields = array();
+
+    // Get fields stored in configuration. If we are explicitly looking for
+    // deleted fields only, this can be skipped, because they will be retrieved
+    // from state below.
+    if (empty($conditions['deleted'])) {
       if (isset($conditions['entity_type']) && isset($conditions['field_name'])) {
         // Optimize for the most frequent case where we do have a specific ID.
         $id = $conditions['entity_type'] . $conditions['field_name'];
@@ -107,9 +112,10 @@ public function loadByProperties(array $conditions = array()) {
         // No specific ID, we need to examine all existing fields.
         $fields = $this->loadMultiple();
       }
+    }
 
     // Merge deleted fields (stored in state) if needed.
-    if ($include_deleted) {
+    if ($include_deleted || !empty($conditions['deleted'])) {
       $deleted_fields = $this->state->get('field.field.deleted') ?: array();
       foreach ($deleted_fields as $id => $config) {
         $fields[$id] = $this->create($config);

core/modules/field/src/FieldInstanceConfigStorage.php

@@ -104,7 +104,12 @@ public function loadByProperties(array $conditions = array()) {
     $include_deleted = isset($conditions['include_deleted']) ? $conditions['include_deleted'] : FALSE;
     unset($conditions['include_deleted']);
 
-    // Get instances stored in configuration.
+    $instances = array();
+
+    // Get instances stored in configuration. If we are explicitly looking for
+    // deleted instances only, this can be skipped, because they will be
+    // retrieved from state below.
+    if (empty($conditions['deleted'])) {
       if (isset($conditions['entity_type']) && isset($conditions['bundle']) && isset($conditions['field_name'])) {
         // Optimize for the most frequent case where we do have a specific ID.
         $id = $conditions['entity_type'] . '.' . $conditions['bundle'] . '.' . $conditions['field_name'];
@@ -114,9 +119,10 @@ public function loadByProperties(array $conditions = array()) {
         // No specific ID, we need to examine all existing instances.
         $instances = $this->loadMultiple();
       }
+    }
 
     // Merge deleted instances (stored in state) if needed.
-    if ($include_deleted) {
+    if ($include_deleted || !empty($conditions['deleted'])) {
       $deleted_instances = $this->state->get('field.instance.deleted') ?: array();
       $deleted_fields = $this->state->get('field.field.deleted') ?: array();
       foreach ($deleted_instances as $id => $config) {