[postgis-users] Who is using PostGIS and how?

Paul Ramsey pramsey at refractions.net
Tue Mar 26 22:08:16 PST 2002


Way cool Ross! To get 5 second responses on Slowaris on such an old
machine is excellent. If you have the opportunity, try out
PostgreSQL/PostGIS on Linux. We have found that the speed increases we
get moving the same app from Slowaris to Linux is actually more than the
MHz multiple difference (ie, moving from a 143Mhz Solaris to 1.43Ghz
Linux will give you much more than a 10 times improvement). Why this is,
I don't know, but we've seen it several times in different contexts --
Solaris/Sparc is better under high loads, but under in light load
situations Linux/x86 whoops its pants.

Searle Ross wrote:
> 
> Paul,
> 
> Sorry about the delay getting back to you.
> 
> We are using PostGIS for an application designed to deliver large
> amounts of natural resource information via a mapserver interface. In
> Queensland our state government has legislation controlling the clearing
> of trees. If a landholder wishes to clear trees he/she has to apply for
> a permit. A permit will only be issued if the clearing does not cause
> environmental degradation. The state government has the role of
> assessing these permits. To do this officers need access to a broad
> range of datasets all generally held in GIS form. The mapserver/PostGIS
> application allows users to quickly search for a parcel of land and
> bring up all the relevant information in a standard format.
> 
> This application was only made possible thanks to PostGIS. The huge size
> of the GIS data sets involved (up to 600 Mb per coverage) meant that a
> mapserver application using shapefiles would have been far too slow or
> complicated if we had gone down the tiling road. The indexing of both
> the spatial and textual data increased response times to very acceptable
> levels. Storing the data in a RDBMS also has many advantages for data
> management as well as the ability to do powerful, flexible querying on
> the fly.
> 
> Some background info
> Hardware : Sun single 143mHz CPU running Solaris
> Database size : approx 2.5 Gig
> Cadastral layer contains approx 1.6 million parcels
> Typical redraw response time : 5 - 10 secs
> Number of users : approx 40
> Number of hits per day : approx 30
> 
> Sorry I can't let you have a look at it but it is behind our firewall,
> so I have included a couple of piccies to help demonstrate what it does
> 
> Regards
> Ross
> 
> 
> 
> -----Original Message-----
> From: Paul Ramsey [mailto:pramsey at refractions.net]
> Sent: Wednesday, 27 March 2002 2:43 AM
> To: postgis-users at postgis.refractions.net
> Subject: [postgis-users] Who is using PostGIS and how?
> 
> Wow, no responses at all the first time!
> 
> OK, there are over 160 of you, someone must be using PostGIS for a real
> application. :) I really do want to hear, since I'll be talking to a
> room full of people whose first reaction will be "what kind of lunatic
> would entrust their business to a product built by people in their spare
> time". I want to be able to say "well, *this* kind of lunatic!"... I
> would also be interested to hear your reasons for selecting PostGIS over
> one of the commercial alternatives.
> 
> I'll go first:
> 
> For example, Refractions is using PostGIS to store and manage a very
> large and highly relational road network database. The use of a RDBMS
> allows us to create different output "snapshots" of the data for
> different users of the road network, since each user has very different
> data standards. A new view of the data is just a new SQL query away.
> Once the data is in a RDBMS, other things become suddenly much easier:
> we have prototyped a geocoder which uses the backend database to convert
> addresses to coordinate information, and used the Mapserver/PostGIS
> connector to visualize the results.
> 
> _______________________________________________




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