Re: 8.x index insert performance

Kelly Burkhart <kelly@tradebotsystems.com> writes:
> On Thu, 2005-11-10 at 19:13 -0500, Tom Lane wrote:
>> Kelly, could there be any patterns in the data that might be
>> related?

> I modified my original program to insert generated, sequential data.
> The following graph shows the results to be flat:
> <http://kkcsm.net/pgcpy_20051111_1.jpg>
> Thus, hardware is sufficient to handle predictably sequential data.

Yeah, inserting sequentially increasing data would only ever touch the
right-hand edge of the btree, so memory requirements would be pretty low
and constant.

> There very well could be a pattern in the data which could affect
> things, however, I'm not sure how to identify it in 100K rows out of
> 100M.

I conjecture that the problem areas represent places where the key
sequence is significantly "more random" than it is elsewhere.  Hard
to be more specific than that though.

            regards, tom lane