[OSM-dev] renderd segfaulting

[Jon Burgess]

On Tue, 2008-08-05 at 12:04 -0700, Mikel Maron wrote:
> 
> > > I've set up mod_tile and renderd. Compiled against mapnik 0.5.1.
> > > 
> > > renderd works for a bit, but then segfaults. It seems to be a
> problem with fielding a burst concurrent requrests, but not certain.
> > > 
> > > Any suggestions on problems to look for?
> > 
> > What compile options did you use for compiling Mapnik? If you set
> > THREADING=single then that could be the problem. It might be worth
> > switching renderd to be single threaded by editing render_config.h
> to
> > NUM_THREADS to 1 and recompile.
> 
> I didn't compile Mapnik with any THREADING option .. assume it
> defaults to multi?
> 
> Changing NUM_THREADS to 1 and recompiling does prevent segfaults.
> Doesn't explain the problem though, and I'd like to get multiple
> threads working, if possible.
> 
> > The code operates fine in multi-threaded mode on the main OSM server
> > which uses the latest SVN mapnik code.
> > 
> > If you still run into problems then it would be good to recompile
> > renderd with debug info by adding -g to the CFLAGS/CXXFLAGS and get
> a
> > backtrace from gdb.
> 
> Running renderd in gdb, it segfaults in "fribidi_remove_bidi_marks"

Ah, multithreading with fribidi would be the problem. From what I
recall, the solution that Artem found was to switch to using libicu
instead :-). This change was made some time ago in SVN but has not
appeared in any release version. I'd recommend moving to the latest SVN
code.

	Jon