In this connection,
https://github.com/facebook/folly/blob/master/folly/docs/FBVector.md
may be relevant. It argues for a 1.5 growth factor.
That has pretty much been refuted by third party testing as far as I'm aware. In my personal experience I found no performance difference between fbvector and libstc++'s.
Actually, no need to look at something like FBVector, the VS2017 STL std::vector implementation uses the following growth policy:
capacity += capacity / 2;
I'm not sure how that used to be, on the MSDN blog (not that long ago) it was noted that an overhaul of std::vector was implemented. I think I remember it used to duplicate before (but cannot verify that anymore).
It used to be closer to 1.5 - I'm glad they changed it. https://stackoverflow.com/questions/12271017/initial-capacity-of-vector-in-c...