WFS on PostGIS: poor performance

[Bart van den Eijnden]

I know Arnulf was having troubles with WFS performance on Oracle Spatial recently, I was tesing PostGIS performance using Mapserver WFS since performance on file-based data was getting too slow, and I figured that would be caused mainly by the lack of attribute indexes. So I switched to PostGIS hoping for a huge increase in performance.

But the improvement of using PostGIS is still not enough for our performance demands (I created all indexes). There are a few things I can do as a WFS client to get better performance, like not sending a condition like nummer like * when the user does not fill in anything for that condition, but that's about all I can do in optimization.

One thing I noticed is that:

* the geometry is collected twice, first of all with the first cursor which returns all records (mycursor), and then with every cursor for every fid (mycursor2). Is this really necessary?

My conclusion so far is, that Mapserver WFS cannot be used with large datasets unfortunately. I hope to be proven wrong though.

Are there any plans left to do something about the Mapserver query mechanism, so that it will work more efficient with database sources?

Arnulf, did you get better performance out of Geoserver, or how did you solve your problems?

Btw I am using latest CVS.

Best regards,
Bart


Bart van den Eijnden
Syncera IT Solutions
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email: BEN at Syncera-ITSolutions.nl