[postgis-devel] Topology construction speed

[Sandro Santilli]

On Tue, Jan 07, 2014 at 03:42:57PM +0000, Graeme B. Bell wrote:

> A concern at the back of my mind is that if the standard topology constructor (or datatype) is using O(n^2) algorithms, are we likely to encounter further similar problems in other functions (perhaps due to similarly written functions elsewhere or due to problems with the underlying datatype)? i.e. is this constructor performance problem the tip of an iceberg?

To my knowledge construction is the most expensive operation.
I'm sure it can be optimized but finding the bottleneck is not an easy task.

> Does anyone know if there have been any tests/measurements of postgis
> topology function performance as datasets get larger?

I remember someone posted a nice graph with timings which didn't look
exponential. But I can't find the link to it right now.

--strk;

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