[Mapserver-dev] Performance loss between 3.5 and 4.2

[Eric Boudaillier]

Hello,

I am a Tcl/Tk developper, newbie in GIS.
For a project, I need a fast shapefile displayer.
I have evaluated some products and found that msworkbench
was the fastest, and moreover uses Tcl/Tk.

The problem is that msworkbench uses an older version
of MapServer (3.5). So I have downloaded:
    freetype 2.1.9
    gd-2.0.28
    MapServer 4.2.3
compiled all that stuff under Windows with VisualC++ 6,
reworked msworkbench to use the new API, and found that...
it was slower.

I have done a simple test with shp2img, which is basically what I need,
that shows the performance loss:

762178 microseconds  home-made v4.2.3 statically linked
854505 microseconds  v3.6.7 binaries
848116 microseconds  v4.2 binaries
378156 microseconds  v3.5 msworkbench dll (compiled with MinGW)

The shapefile represents USA and is 18Mo.

Could someone explain these differences ?
Could the compilation with MinGW give better result ?
Or is 3.5 just faster ? If so, is there some inconvenient to use this
version for my need ?
Then, where can I download a source package of 3.5 ?

Thanks for your help.

-- 
-eric