[mapserver-users] Image Speed Questions---Generic

[Doug Nebert]

Walt Lin wrote:
> 
> On the note of trivial rejection and tileindices, what about this solution: store the extents of all the different shapefiles (perhaps one per county on a national level) in a postgres table with an R-Tree index.  When a request comes in, query Postgres for all the shapefiles that intersect and load them using mapserver.  Of course, POSTGIS would be optimal, storing everything in Postgres, but from what I've heard this is really slow in practice.  Thoughts?
> 
> Walt

Actually a simpler technique is quite feasible: If you request a map
using the exact same URL (extents, layers, etc) then a caching 
webserver will provide the map from the cache instead of requesting
it. I have seen this work quite well on all sizes of datasets. By
having pre-set extents, such as counties, you can encourage this
behavior.

Doug.
-- 
Douglas D. Nebert
Geospatial Data Clearinghouse Coordinator 
FGDC/GSDI Secretariat	Phone: +1 703 648 4151	Fax: +1 703 648-5755	
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