Hi, Thank you for your question.
For large, frequently updated datasets in Ignite UI for Angular, the following approaches are effective:

1. Virtualization
   All Ignite UI grids have row and column virtualization enabled by default. To ensure virtualization works correctly, make sure to set a fixed height on the grid element.
   -> Angular Grid Virtualization and Performance – Ignite UI for Angular
2. Remote Data Operations (Server-side Sorting & Filtering)
   When data updates frequently, use NoopSortingStrategy and NoopFilteringStrategy to delegate sorting and filtering to the server. This prevents unnecessary client-side reprocessing and keeps the grid responsive.
   -> Angular Grid Remote Data Operations – Ignite UI for Angular
3. Virtual Scrolling + Lazy Loading
   Use the (dataPreLoad) event to fetch only the data within the visible range on scroll, and bind [totalItemCount] to ensure the scrollbar is rendered accurately. Combining this with RxJS debounceTime is also recommended to avoid overloading the server with rapid consecutive requests.
   ->Angular Grid Paging | Angular Pagination Table | Infragistics

I hope these suggestions help improve the responsiveness of your grid. Please feel free to reach out if you have any further questions!

Best regards,
Tom