I wrote:
> That is not the number of interest. The number of interest is that it's
> 8 bytes added onto a struct that currently contains 11 of 'em; in other
> words a 9% increase in the size of the stats file, and consequently
> about a 9% increase in the cost of updating it.
Wups, sorry, I was looking at the wrong struct. It's actually an
addition of 1 doubleword to a struct of 21 of 'em, or about 5%.
That's still an awful lot in comparison to the prospective usefulness
of the information.
regards, tom lane