[mapserver-users] Raster performance hints

[Ziegler Stefan]

Hi

We are using MapServer for vector data stored in a PostgreSQL/PostGIS database. For a new project we are planning to provide a WMS based on raster layers and therefore in need of some performance hints or your experiences.

The raw data will be a lot of single GeoTIFF (aerials, hillshading, slopes, etc.) files, like 5'000 - 10'000 from different organizations. Since the originate from different organizations it's possible that they can have different resolutions. Conceptionally for aerials it would look like this:

Aerial group
|_ aerial from organization one (1000 single tiffs, resolution 10cm, approx 10k x 10k pixels)
|_ aerial from organization two (600 single tiffs, resolution, 12.5 cm, approx 10k x 10k pixels)
|_ aerial from organization three (3000 single tiffs, resolution, 10 cm, approx 10k x 10k pixels)

For some hundred single GeoTIFFs we have good experience with the Tileindex approach and an handmade external overview that kicks in at smaller scale.

Will this approach still work with a massive amount of single tiffs? Or are the better ones? What about the compression (quality vs. decompression speed vs. disk space?) Or would you expect a much better performance with - let's say - a BigTIFF for each organisation?

Thanks for any hints.

Best regards
Stefan

Freundliche Grüsse
 
Stefan Ziegler 
Kantonsgeometer / Leiter Amt für Geoinformation

Amt für Geoinformation
Rötistrasse 4 
4500 Solothurn 

Telefon +41 32 627 75 96
stefan.ziegler at bd.so.ch
http://www.so.ch