Topic: output stopping after 4096 bytes

[johncallahan]

Strange issue here. I'm running Windows 2008 Server x64 version. I downloaded the apache 2.2.11 x64 binaries from http://www.blackdot.be/?inc=apache/binaries.

(I also php x64 installed from http://www.fusionxlan.com/PHPx64.php but that may not be relevant here.)


I'm running a cgi program called MapServer, it's for generating maps on the fly from multiple source spatial data sets. I'm running the x64 version downloaded from http://vbkto.dyndns.org:1280/sdk/ (the MSVC2005 (Win64) -stable version)

The following URL should return an XML file. It starts the response but cuts off after 4096 bytes (including header)

http://dev.dgs.udel.edu/cgi-bin/mapserv.exe?map=C:\webgis\mapfiles\geomap08.map&SERVICE=WMS&VERSION=1.1.1&REQUEST=GetCapabilities


When I run the same from the Windows command line into an XML file, the same issue occurs:

c:\Apache2.2\cgi-bin\mapserver.exe "QUERY_STRING=map=c:/webgis/mapfiles/geomap12.map&SERVICE=WMS&VERSION=1.1.1&REQUEST=GetCapabilities > output.xml


However, if I let the output go to the screen and not to a file, it works great.

c:\Apache2.2\cgi-bin\mapserver.exe "QUERY_STRING=map=c:/webgis/mapfiles/geomap12.map&SERVICE=WMS&VERSION=1.1.1&REQUEST=GetCapabilities (this works!)


Any ideas what to try? Are there apache server settings or Win2008 settings/variables I can try? Thanks for ANY help you can provide. I'm stuck.

- John



PS - MapServer seems to work when it returns images/maps. I also never had any problems with these same mapserver map files on my Win32 boxes. This is the first time I'm going all x64. I just don't know where the error is actually taking place.

[James Blond]

Things you can check in your php.ini:

output_buffering

Often output_buffering is set to 4096 bytes. Maybe you have to set a higher limit.

Anything in apache error.log? Did you enable PHP error log? If yes anything in it about this error?

Than

max_execution_time
max_input_time
memory_limit
post_max_size

[johncallahan]

Thanks for the thoughts. However, I have changed output_buffering to 8k and 16k with no luck. The other parameters also are more than enough.

Nothing in the apache or php error logs, and I have them set to E_ALL and debug, respectively.

Would PHP be involved at all? I don't know. This is a exe file (mapserv.exe) that runs as a cgi-bin script. I run the exe file directly in the browser or command line.


- John

[johncallahan]

When I run the exact same app from my WinXP x64 (SP2) box, all works great. I had copied the exact same file structure (of apache, PHP, mapserver) from Win2008 to WinXP.

So, of course, it's something with my Win2008 Server setup. The Win2008 machine is actually a VM if that matters.

[James Blond]

Whoops! I didn't see that it was cgi and not PHP related

I think you should try to debug it with in included debugger. See http://httpd.apache.org/docs/2.2/mod/mod_cgi.html#cgi-debug

Hope that helps.

[johncallahan]

Thanks for the link. I didn't know of ScriptLog. Unfortunately (or fortunately) I can't get anything written to the log file. My guess is that apache thinks everything is working fine.

I know have my exact same app on four machines, all with the exact same setup, versions, file structure. It works great on a WinXP x64 box and Win2008 x64 box. It doesn't work (truncates at 4096 bytes) on two WIn2008 x64 boxes.

So, I'm trying to figure out the differences among the hardware, security and network setups. It's likely not an apache issue if I have the same httpd.conf file on all four machines.

One thought is a mime type issue. I haven't tested much but I see the truncation only with a XML file.

Oh well, I'll keep working on it. Thanks for your help!