[mapserver-dev] mappostgis.c

[Paul Ramsey]

It's not mapfile parsing, it's pj_init. Try just turning the
PROJECTION entries from init=epsg to the proj literials.

P.

On Tue, Nov 4, 2008 at 10:09 PM, thomas bonfort
<thomas.bonfort at gmail.com> wrote:
> I had a go on the geoserver-vs-mapserver test-data, for the simple
> shapefile case.
>
> My quick experimenting with shp2img was that the rendering time for a
> single image could pass from around .12s using the supplied mapfile,
> to around .05s using a cleaned up mapfile with the unused layers
> removed.
>
> Do we have any alternatives on the parser front, as I think it is also
> a clear weakpoint we have when compared to geoserver on such simple
> maps.
>
> thomas
>
> On Tue, Nov 4, 2008 at 23:36, Paul Ramsey <pramsey at cleverelephant.ca> wrote:
>> On Tue, Nov 4, 2008 at 10:54 AM, Steve Lime <Steve.Lime at dnr.state.mn.us> wrote:
>>> A good threat, probably long overdue. Do you have any feel for the performance end of things? I
>>> recall the Geoserver tests showing GeoServer performing substantially better than MapServer w/regards
>>> to PostGIS.
>>
>> OK, this isn't testing against Geoserver, just against 5.2, and the
>> result is, 5.4trunk is maybe 5% slower. Which is not unsurprising,
>> since now the geometry is transiting a text encoding on the way. I had
>> my fingers crossed that the simpler database handling would speed
>> things up, but no go.
>>
>> In terms of straight-up profiling information:
>>
>> 25% of cycles are still spent in pj_init, and this is *after* I moved
>> the two relevant EPSG codes to the top of the file. Geoserver has
>> objects cached.
>> 20% of cycles are spent in image compression (gif or png). The
>> Geoserver ImageIO might have optimized image compressors (my work with
>> IPP impresses on me how much gain is available in this area).
>>
>> The penalty for parsing the proj4 definitions every time, even for
>> layers that aren't being drawn, is certainly high, and of course grows
>> the more layers you have.  However, these overheads also exist in the
>> shape file chain, so the difference between PostGIS and Shape relative
>> to Geoserver remains unexplained.
>>
>> P.
>> _______________________________________________
>> mapserver-dev mailing list
>> mapserver-dev at lists.osgeo.org
>> http://lists.osgeo.org/mailman/listinfo/mapserver-dev
>>
> _______________________________________________
> mapserver-dev mailing list
> mapserver-dev at lists.osgeo.org
> http://lists.osgeo.org/mailman/listinfo/mapserver-dev
>