Segmentation fault - mapserver - postgis

[Nilsson Bengt]

 Hi,

I'm not sure that it's a fastcgi problem.

As you can see from the postgresql log, postgresql reports a 
warning: 'WARNING:  25001: there is already a transaction in progress'.

The cause of that, I guess, is that mapserver, in mappostgis.c, sends 
(another) 'BEGIN'. During the first call it also sent a BEGIN. In
mappostgis.c 
there is a check on the outcome of the BEGIN (if(!result ||
PQresultStatus
(result) != PGRES_COMMAND_OK) { ) and I guess that it won't be OK
because 
of the warning.

Digging around in the postgresql.conf file gave me an idea of changing 
the '#client_min_messages = notice' to 'client_min_messages = error'. As
I 
understand that means that postgresql won't report warnings back to the 
client, mappostgis, and thus the test won't fail.

I haven't got any 'Segmentation faults' from the application when
running it as a static server since my change so I guess I'm on the
right track. 

I wonder why mapserver sends repeating BEGINs and no ENDs. I 
can't find any code for sending an END. Normally, no fastcgi with
persistant 
connections, it won't matter since I guess that a closed connection also

means 'END'.



/Regards Bengt 

-----Original Message-----
From: UMN MapServer Users List [mailto:MAPSERVER-USERS at LISTS.UMN.EDU] On
Behalf Of Frank Warmerdam
Sent: den 13 september 2007 14:48
To: MAPSERVER-USERS at LISTS.UMN.EDU
Subject: Re: [UMN_MAPSERVER-USERS] Segmentation fault - mapserver -
postgis

Bengt Nilsson wrote:
> Hi,
> 
> I'm trying to run mapserver as a static fastcgi (WMS)application but 
> gets Segmenttaion fault every second time I request a map from the 
> server. After that, the fastcgi server is restarted and works for one 
> request again, and so on..
> 
> My configuration is Apache 2.2.6, mod_fastcgi 2.4.2, mapserver 4.10.0,

> postgis 1.2.1, postgresql 8.1.4

Bengt,

I would be willing to follow up on this issue privately as I suspect an
issue in my fastcgi implementation within MapServer.  It would be
helpful if you could file a bug report and attach a mapfile, and dump of
a minimal
table sufficient to reproduce the problem.   Please assign the problem
directly to me (userid "warmerdam").

I would also appreciate it if you could test the problem with the
current MapServer RC though that isn't strictly necessary.

Best regards,
-- 
---------------------------------------+--------------------------------
---------------------------------------+------
I set the clouds in motion - turn up   | Frank Warmerdam,
warmerdam at pobox.com
light and sound - activate the windows | http://pobox.com/~warmerdam
and watch the world go round - Rush    | President OSGeo,
http://osgeo.org