Fixed: UI slowdowns while tasks are running

Fixes #3480

frontend/src/Store/Actions/Creators/createHandleActions.js

@@ -72,18 +72,31 @@ export default function createHandleActions(handlers, defaultState, section) {
       if (section === baseSection) {
         const newState = getSectionState(state, payloadSection);
         const items = newState.items;
-        const index = _.findIndex(items, { id: payload.id });
+
+        if (!newState.itemMap) {
+          newState.itemMap = createItemMap(items);
+        }
+
+        const index = payload.id in newState.itemMap ? newState.itemMap[payload.id] : -1;
 
         newState.items = [...items];
 
         // TODO: Move adding to it's own reducer
         if (index >= 0) {
           const item = items[index];
+          const newItem = { ...item, ...otherProps };
 
-          newState.items.splice(index, 1, { ...item, ...otherProps });
+          // if the item to update is equal to existing, then don't actually update
+          // to prevent costly reselections
+          if (_.isEqual(item, newItem)) {
+            return state;
+          }
+
+          newState.items.splice(index, 1, newItem);
         } else if (!updateOnly) {
-          newState.items.push({ ...otherProps });
-          newState.itemMap = createItemMap(newState.items);
+          const newIndex = newState.items.push({ ...otherProps }) - 1;
+
+          newState.itemMap[payload.id] = newIndex;
         }
 
         return updateSectionState(state, payloadSection, newState);

frontend/src/Store/Selectors/createSeriesClientSideCollectionItemsSelector.js

@@ -1,6 +1,6 @@
-import { createSelector } from 'reselect';
-import createDeepEqualSelector from './createDeepEqualSelector';
+import { createSelector, createSelectorCreator, defaultMemoize } from 'reselect';
 import createClientSideCollectionSelector from './createClientSideCollectionSelector';
+import hasDifferentItemsOrOrder from 'Utilities/Object/hasDifferentItemsOrOrder';
 
 function createUnoptimizedSelector(uiSection) {
   return createSelector(
@@ -26,8 +26,17 @@ function createUnoptimizedSelector(uiSection) {
   );
 }
 
+function seriesListEqual(a, b) {
+  return hasDifferentItemsOrOrder(a, b);
+}
+
+const createSeriesEqualSelector = createSelectorCreator(
+  defaultMemoize,
+  seriesListEqual
+);
+
 function createSeriesClientSideCollectionItemsSelector(uiSection) {
-  return createDeepEqualSelector(
+  return createSeriesEqualSelector(
     createUnoptimizedSelector(uiSection),
     (series) => series
   );

src/Sonarr.Api.V3/Series/SeriesResource.cs

@@ -50,7 +50,6 @@ namespace Sonarr.Api.V3.Series
         public int TvRageId { get; set; }
         public int TvMazeId { get; set; }
         public DateTime? FirstAired { get; set; }
-        public DateTime? LastInfoSync { get; set; }
         public SeriesTypes SeriesType { get; set; }
         public string CleanTitle { get; set; }
         public string ImdbId { get; set; }
@@ -109,7 +108,6 @@ namespace Sonarr.Api.V3.Series
                        TvRageId = model.TvRageId,
                        TvMazeId = model.TvMazeId,
                        FirstAired = model.FirstAired,
-                       LastInfoSync = model.LastInfoSync,
                        SeriesType = model.SeriesType,
                        CleanTitle = model.CleanTitle,
                        ImdbId = model.ImdbId,
@@ -167,7 +165,6 @@ namespace Sonarr.Api.V3.Series
                        TvRageId = resource.TvRageId,
                        TvMazeId = resource.TvMazeId,
                        FirstAired = resource.FirstAired,
-                       LastInfoSync = resource.LastInfoSync,
                        SeriesType = resource.SeriesType,
                        CleanTitle = resource.CleanTitle,
                        ImdbId = resource.ImdbId,