millions of columns in a row vs millions of rows with one column

[Héctor Izquierdo Seliva]

Hi Everyone.

I'm testing performance differences of millions of columns in a row vs
millions of rows. So far it seems wide rows perform better in terms of
reads, but there can be potentially hundreds of millions of columns in a
row. Is this going to be a problem? Should I go with individual rows? I
run 6 nodes with 7.2 and a RF=3.

Thanks for your help!