[MS4W-Users] php-cgi crash with PostGIS

[Johan Forsman]

Hello All:

I do not know what the proper place to report this issue may be, but I thought I would start here hoping you can steer me in the right direction.

We have a small, internal to my organization, mapserver on WinXP, currently using MS4W 3.0 beta 6, with GeoMoose 2.0.1, primarily with shapefiles. The query function in GeoMoose is too slow for practical use for a particular point-data set and it was suggested by the developers to try the PostGIS system instead to speed up response time of the query.

I installed and configured PostgreSQL 8.4.0 and PostGIS 1.4 without issues, and I am using pgAdmin to help me along with configuration. I created a new database "sdwp" instead of using the default "postgres" database

I ingested the shapefile into PostGIS without issues and built an index on the field of interest to the query, then changed the mapfile to point to PostGIS instead of the shapefile.

Display of data from PostGIS works fine, but every time I execute the query there is a crash of php-cgi.exe on the server. The message on the server is the generic crash message from WinXP: CGI/FastCGI has encountered a problem and needs to close.

One strange thing is that the crash occurs in two separate modules depending on which dataset I query against.

Dataset A: Full dataset of ~180000 water wells.
Dataset B: Subset of dataset A, ~20000 water wells.

Both are point data, and were ingested from individual shapefiles, and are currently stored as separate tables in the same PostGIS database, with separate indexes.

For dataset A the crash first occurs in gdal17dev.dll, then repeatedly in ntdll.dll shortly after clicking the "Don't Send" button (Remote Desktop control). I click the Don't Send button several times to dismiss the crash dialogs that pop up.

For dataset B the crash occurs only in ntdll.dll, and only once per query attempt.  

Once the crash has occurred I click the Don't Send button in the crash dialog on the server and one of two things will happen depending on the active dataset. 

Dataset A: 1) if there ARE NO matches for the query parameter GeoMoose immediately returns a message to that effect; 2) if there ARE matches to the query parameter GeoMoose returns the correct number of records.

Dataset B: 1) if there ARE NO matches for the query parameter GeoMoose immediately returns a message to that effect; 2) if there ARE  matches to the query parameter the server returns an Unhandled Request return, Internal Server Error message after a several-second delay.

There are more permutations than the above if I change the "turn highlight layer on" and/or "zoom to first hit" properties inside of the GeoMoose mapbook.

I don't even know where to start collecting evidence. Red herrings everywhere I suspect. This problem does not appear if I use shapefiles, but the query takes too long for practical use. PHP issue? GeoMoose issue? Mapserver issue? Windows issue? PostGIS issue? Yes to all or some of that?

There is an error shown in the PostGIS log, but I do not know if it is relevant (symptom or disease):

2009-12-03 09:23:24 CSTLOG:  could not receive data from client: No connection could be made because the target machine actively refused it.	
2009-12-03 09:23:24 CSTLOG:  unexpected EOF on client connection	

What information do I need to collect, how do I collect it, and where should I send it to help with resolving this?

Thank you for your consideration.

Respectfully,
Johan.

----------------------
Johan Forsman
Geologist
Safe Drinking Water Program
Louisiana Department of Health and Hospitals
Office of Public Health
Telephone: 225.342.7309
Telefax: 225.342.7303