That's exactly why the geometry instancing exists.

According to my experience, it boosts performance a lot.


renanse said:

Modern graphics cards hate getting lots and lots of small meshes.  If you can replace these with a few large meshes, you'll run much better.

Thanks for answering.

Yes, in theory it should speed up. But I was also interested in if anyone actually used it in any game? 

I have now implemented it for most of the static scene and got a nice speedup from 100 fps to 250 fps. Now time to focus on optimizing the dynamic part of the scene…