HarmonyOS 使用PersistentStorage本地持久化存储一段40kb左右的字符串存储失败，重新打开app时值仍为空

windowStage.loadContent('pages/Index', (err, data) => {  
  if (err.code) {  
    hilog.error(0x0000, 'testTag', 'Failed to load the content. Cause: %{public}s', JSON.stringify(err) ?? '');  
    return;  
  }  
  let window = windowStage.getMainWindow();  
  window.then(win => {  
    let uiContext = win.getUIContext();  
    uiContext.runScopedTask(() => {  
      PersistentStorage.persistProp('aProp', 47);  
    })  
  })  
  hilog.info(0x0000, 'testTag', 'Succeeded in loading the content. Data: %{public}s', JSON.stringify(data) ?? '');  
});