[Benchmarking] Vector data

[Jeff McKenna]

Andrea Aime wrote:
> GeoServer cannot load a set of separate .shp files as a single entity.
> Mind this data set comes from the original RR test thought, I've
> never touched it.
> 
> If you think splitting it up in parts will lead to better performance
> you should try out that and we can see how much faster things become?

Great idea.  In fact I spent some time and generated a new vector test 
dataset for the state of Texas using the TIGER 2008 release.  I am 
uploading this now so we can all access it:

vector-data-tiger08-tx-merged (1.1GB)
  - contains merged files for the entire state

vector-data-tiger08-tx-counties.zip (1.1GB)
  - files stored in individual county folders (as released by the US Census)

I have updated the benchmarking wiki with descriptions of each shapefile 
(http://wiki.osgeo.org/wiki/Benchmarking_2009) and I have also updated 
the roads styles page for the new classifications 
(http://wiki.osgeo.org/wiki/Texas_roads_styled)

My initial tests with MapServer 5.5.0 (dev) are surprising to me:
- loading merged shapefiles for entire state (>1 GB) are faster than by 
using tileindexes to access individual counties

e.g.

merged: 
http://labs.gatewaygeomatics.com/cgi-bin/wms_benchmarking_by_merged?SERVICE=WMS&VERSION=1.1.1&REQUEST=getmap&layers=vector_benchmarking&STYLES=&SRS=EPSG:4269&BBOX=-96.980629943844,29.854114257812,-96.79038641357,29.974268066406&WIDTH=950&HEIGHT=600&FORMAT=image/png

by county: 
http://labs.gatewaygeomatics.com/cgi-bin/wms_benchmarking_by_county?SERVICE=WMS&VERSION=1.1.1&REQUEST=getmap&layers=vector_benchmarking&STYLES=&SRS=EPSG:4269&BBOX=-96.980629943844,29.854114257812,-96.79038641357,29.974268066406&WIDTH=950&HEIGHT=600&FORMAT=image/png

Questions:

- what scales should I be focusing on for styling? (or are we only 
testing the extents that are listed in the Wiki, of La Grange?)
- I need some feedback on what other layers I should style (such as 
pointlm, arealm)...if no feedback i'll just go ahead and come up with 
styles for those

thanks.

-jeff