fix performance regression for Site save, use bulk_update for cached fields

netbox/dcim/forms/model_forms.py

@@ -733,10 +733,9 @@ class ModuleForm(ModuleCommonForm, PrimaryModelForm):
     )
     module_bay = DynamicModelChoiceField(
         label=_('Module bay'),
-        queryset=ModuleBay.objects.order_by('name'),
+        queryset=ModuleBay.objects.all(),
         query_params={
-            'device_id': '$device',
-            'ordering': 'name',
+            'device_id': '$device'
         },
         context={
             'disabled': 'installed_module',

netbox/dcim/signals.py

@@ -211,12 +211,16 @@ def sync_cached_scope_fields(instance, created, **kwargs):
     for model in (Prefix, Cluster, WirelessLAN):
         qs = model.objects.filter(**filters)
 
+        # Bulk update cached fields to avoid O(N) performance issues with large datasets.
+        # This does not trigger post_save signals, avoiding spurious change log entries.
+        objects_to_update = []
         for obj in qs:
             # Recompute cache using the same logic as save()
             obj.cache_related_objects()
-            obj.save(update_fields=[
-                '_location',
-                '_site',
-                '_site_group',
-                '_region',
-            ])
+            objects_to_update.append(obj)
+
+        if objects_to_update:
+            model.objects.bulk_update(
+                objects_to_update,
+                ['_location', '_site', '_site_group', '_region']
+            )

netbox/project-static/src/select/classes/dynamicTomSelect.ts

@@ -75,16 +75,10 @@ export class DynamicTomSelect extends TomSelect {
   load(value: string) {
     const self = this;
 
-    // Save current selection before clearing
-    const currentValue = self.getValue();
-
     // Automatically clear any cached options. (Only options included
     // in the API response should be present.)
     self.clearOptions();
 
-    // Clear user_options to prevent the pre-selected option from being treated specially
-    (self as any).user_options = {};
-
     // Populate the null option (if any) if not searching
     if (self.nullOption && !value) {
       self.addOption(self.nullOption);
@@ -104,29 +98,16 @@ export class DynamicTomSelect extends TomSelect {
       .then(response => response.json())
       .then(apiData => {
         const results: Dict[] = apiData.results;
-
-        // Add options and manually set $order to ensure correct sorting
-        results.forEach((result, index) => {
+        const options: Dict[] = [];
+        for (const result of results) {
           const option = self.getOptionFromData(result);
-          self.addOption(option);
-          // Set $order after addOption() to override any special handling of pre-selected items
-          const key = option[self.settings.valueField as string] as string;
-          if (self.options[key]) {
-            (self.options[key] as any).$order = index;
-          }
-        });
-
-        self.loading--;
-        if (self.loading === 0) {
-          self.wrapper.classList.remove(self.settings.loadingClass as string);
+          options.push(option);
         }
-
-        // Restore the current selection
-        if (currentValue && !self.items.includes(currentValue as string)) {
-          self.items.push(currentValue as string);
-        }
-
-        self.refreshOptions(false);
+        return options;
+      })
+      // Pass the options to the callback function
+      .then(options => {
+        self.loadCallback(options, []);
       })
       .catch(() => {
         self.loadCallback([], []);

netbox/project-static/src/select/dynamic.ts

@@ -49,9 +49,6 @@ export function initDynamicSelects(): void {
       labelField: LABEL_FIELD,
       maxOptions: MAX_OPTIONS,
 
-      // Preserve API response order
-      sortField: '$order',
-
       // Disable local search (search is performed on the backend)
       searchField: [],