Framework: Vaadin 8 Grid is 5 times slower than Vaadin 7 to render columns

[neerup]

• Upgraded Vaadin 7.7.7 to Vaadin 8.0.0 in my project.
  And now rendering of grids is very slow.
  In my application performance has gone from 1.5 Sec to 8 Sec to render 80 columns,
  even when there is no data to show.
  This makes migrating to 8.0.0 imposible

• Is there any work around for this?

• I'm using Vaadin version 8.0.0

• Minimal reproducible example
  Add this grid to UI

  Grid<String> grid = new Grid<>();
  grid.setSizeFull();
  for (int i = 0; i < 80; i++) {
      grid.addColumn(row -> "novalue").setCaption("Column_" + i).setWidth(200);
  }
  

[macjuan]

There were other reports claiming Grid in 8 is 10 times slower to render. Pretty interesting, especially when I thought that Grid was pretty much the same in 7 and 8.

[hesara]

There seem to be issues at attach time (very large number of forced reflows on the client side) when the grid has a large number of columns - already investigating this.

[hesara]

Preliminary test results for #8848 tests after fixes, grid with 80 columns and 10 rows.
Note that the times are for slow test VMs - significantly faster on a fast local browser.

Browser | V7 Compatibility Grid | 8.0.2 V8 Grid | V8 Grid (optimized)
----------- | ---------------------------- | ------------------ | --------------------------
PhantomJS | 2963 ms | 57690 ms | 1657 ms
Chrome | 3305 ms | 33604 ms | 1894 ms
Firefox 45 | 6185 ms | >60s | 2418 ms
IE11 | 5652 ms | 33861 ms | 2262 ms

[acsadam0404]

This is still not working correctly. Testing with vaadin 8.1. I made a minimal example that shows that v8 grid is much slower than the v7 table. I don't have measurements as I don't know how can I measure the rendering time, but simply doing a browser refresh on both project is self explanatory.

grids.zip

[scrmtrey91]

Yeah grid is still very slow (thus the UI loading is slower).

[brunojcm]

I still feel the same, using Vaadin 8,1.4 TreeGrid. It used to be faster in V7, even with bigger grids.

[jsalts]

Very slow. 20 tables x 8 columns with no data takes about 8 seconds to load. Using 8.1

[acsadam0404]

Opened a new issue for this https://github.com/vaadin/framework/issues/10232 because this one don't have enough attention.