[mapserver-users] MapServer 4.8.3: MapScript setProjection

[Simon Greig]

Thank you for the responses Daniel and Frank.

We have implemented the following changes:
Removed all setting of projection in individual layers
Moved the <27700> projection to the top of the epsg file
Reverted back to mapobj.setProjection ("init=epsg:27700") in the code

We have run some tests in our development environment and these changes 
remove the error we were seeing and still produces valid map images.  We 
are going to run some performance tests overnight in our pre-production 
environment against 200 or so of our layers to see what impacts we get 
against our live data. 

I am expecting an improvement because we used to call set projection once 
for the map and then once for each of our 18 context layers in each WMS 
request.  So if setProjection took ~200ms before, that meant our 
setprojection process was taking (200+(18*200)) =  ~3.8 seconds for each 
request.  Now the worst case is 200ms for the map set projection and 
because of the epsg file change hopefully that will come down to <100ms 
per request.

Next week we plan to filter out the context layers that we know will not 
get drawn at the view scale right at the start of processing so we expect 
more savings.

Thanks for the support.  Simon






Unless stated otherwise above:
IBM United Kingdom Limited - Registered in England and Wales with number 
741598. 
Registered office: PO Box 41, North Harbour, Portsmouth, Hampshire PO6 3AU





-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.osgeo.org/pipermail/mapserver-users/attachments/20080328/0af85d14/attachment.html