Sync v2 performance, initial sync limit=1

src/@types/global.d.ts

@@ -51,6 +51,7 @@ import ActiveWidgetStore from "../stores/ActiveWidgetStore";
 import AutoRageshakeStore from "../stores/AutoRageshakeStore";
 import { IConfigOptions } from "../IConfigOptions";
 import { MatrixDispatcher } from "../dispatcher/dispatcher";
+import { MessagePreviewStore } from "../stores/room-list/MessagePreviewStore";
 
 /* eslint-disable @typescript-eslint/naming-convention */
 
@@ -109,6 +110,7 @@ declare global {
         mxLoginWithAccessToken: (hsUrl: string, accessToken: string) => Promise<void>;
         mxAutoRageshakeStore?: AutoRageshakeStore;
         mxDispatcher: MatrixDispatcher;
+        mxMessagePreviewStore: MessagePreviewStore;
     }
 
     interface Electron {

src/MatrixClientPeg.ts

@@ -127,7 +127,9 @@ class MatrixClientPegClass implements IMatrixClientPeg {
     // at any time up to after the 'will_start_client'
     // event is finished processing.
     public opts: IStartClientOpts = {
-        initialSyncLimit: 20,
+        // We ask for only a single timeline event per-room in the initial sync to make it faster.
+        // We'll eagerly backfill rooms after this initial sync.
+        initialSyncLimit: 1,
     };
 
     private matrixClient: MatrixClient = null;

src/components/views/settings/EventIndexPanel.tsx

@@ -125,7 +125,7 @@ export default class EventIndexPanel extends React.Component<{}, IState> {
 
         await EventIndexPeg.initEventIndex();
         await EventIndexPeg.get().addInitialCheckpoints();
-        EventIndexPeg.get().startCrawler();
+        EventIndexPeg.start();
         await SettingsStore.setValue('enableEventIndexing', null, SettingLevel.DEVICE, true);
         await this.updateState();
     };