Mapscript crashing Tomcat --> [Panic]

[Umberto Nicoletti]

This problem with GD has been a long-standing issue and it is worsened
by the fact that gd development stalled for quite some time. Gd 2.0.34
is a most welcome release!

Umberto

On 3/29/07, Rodrigo Del C. Andrade <rodrigo.andrade at digitro.com.br> wrote:
>
>     Dear Frank and Umberto:
>
>     Thanks a lot for the advice, you really nailed it. I haven't tried
> reproducing it on mapserver cgi yet, but upgrading GD to 2.0.34 (I had
> 2.0.33) apparently did the trick.
>     I am testing it as I type, but it has been running for 20 min now
> and it haven't crashed yet, as opposed to the 20 secs crash.
>     I tracked down that linux machine where it used to work fine and
> sure enough, that one had the newer GD in it.
>
>     Thanks a whole lot.
>     Sincerely
>
>     Rodrigo
>
> Umberto Nicoletti wrote:
> > On 3/28/07, Frank Warmerdam <warmerdam at pobox.com> wrote:
> >> Rodrigo Del C. Andrade wrote:
> >> >      Greetings. dear list.
> >> >      We are experiencing some troubling difficulties developing an
> >> > application with mapscript on a Java web based environment with
> >> tomcat.
> >> >    Here is the deal: while using the app (not nearly done, but
> >> > functional enough at this stage) when one tries to zoom (in or out) or
> >> > pan the map more than a few times, Tomcat often will go down screaming
> >> > and the JVM just gives up on life.
> >> >    I know this is probably not the right or best place to ask about
> >> it,
> >> > but it seems to be caused by the interaction of mapscript and the GD
> >> > library.
> >> >         Here is the JVM output short version (long version is attached
> >> > at the bottom):
> >> ...
> >> >    Any ideas? Full JVM error log is at the bottom. I am ready to
> >> give in
> >> > more info if needed.
> >> >    Thanks in advance;
> >> ...
> >>
> >> > Stack: [0xb0203000,0xb0284000),  sp=0xb0279ed4,  free space=475k
> >> > Native frames: (J=compiled Java code, j=interpreted, Vv=VM code,
> >> > C=native code)
> >> > C  [libgd.so.2+0x8182]
> >> > C  [libgd.so.2+0x9a16]  gdImageLine+0x4a6
> >> > C  [libmapscript.so+0xad355]
> >> > C  [libmapscript.so+0xb310e]  msDrawLineSymbolGD+0xe7e
> >> > C  [libmapscript.so+0xa75fb]  msDrawLineSymbol+0x8b
> >> > C  [libmapscript.so+0xa9cb2]  msDrawShape+0x17e2
> >> > C  [libmapscript.so+0xaa6d8]  msDrawVectorLayer+0x398
> >> > C  [libmapscript.so+0xaa97a]  msDrawLayer+0xaa
> >> > C  [libmapscript.so+0xaba67]  msDrawMap+0x6a7
> >> > C  [libmapscript.so+0x552b5]
> >>
> >> Rodrigo,
> >>
> >> I'd suggesting seeing if you can reproduce this without Java
> >> involved.  I
> >> suspect there is some sort of memory error in msDrawLineSymbolGD()
> >> (possibly
> >> the infamous antialiasing bug?).
> >
> > Frank,
> > I bet it is exactly that!
> > Rodrigo: upgrade to gd 2.0.34 (http://www.libgd.org/Main_Page) and
> > tell us if the problem goes away.
> >
> > Umberto
> >
> >>
> >> Capture your map configuration into a map file, and run the map through
> >> shp2img or mapserv with the appropriate layers turned on, and similar
> >> view configuration *and* run it under "valgrind" to quickly highly
> >> memory corruption as soon as it happens.
> >>
> >> If you can reproduce it this way,then you have something you can file
> >> as a bug report.
> >>
> >> MapServer is not bug free, and it is important to be able to narrow
> >> down bugs without too much extraneous stuff.
> >>
> >> 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
> >>
> >
> >
>