Robert Barry

Thanks for your suggestion that it is not a grape vine.  It was sold to me as Coignetiae - Giant Crimson Glory Vine.

However, following up on your suggestion I think I have found its true identity:

Porcelain Berry (Ampelopsis brevipedunculata)

https://florapittsburghensis.wordpress.com/2013/10/23/porcelain-berry-ampelopsis-brevipedunculata/

I planted this grape vine 4 year ago.  About a year later my dog chewed through the main stem.  The vine then grew very vigorously, without producing bunches of grapes.  Instead I get these tiny berry like fruits - see photo.  Any suggestions as to how to improve this situation gratefully received.