GammaLib

When running ctobssim, a similar problem occurs:

(gdb) backtrace
#0  0x0000003e8d86fac1 in fseeko64 () from /lib64/libc.so.6
#1  0x00007ffff7317bc5 in file_seek ()
   from /afs/ifh.de/group/hess/scratch/software/stable/cfitsio/sl6/cfitsio-3.340-gcc-4.8.1/lib/libcfitsio.so
#2  0x00007ffff7317db2 in file_write ()
   from /afs/ifh.de/group/hess/scratch/software/stable/cfitsio/sl6/cfitsio-3.340-gcc-4.8.1/lib/libcfitsio.so
#3  0x00007ffff7312404 in ffwrite ()
   from /afs/ifh.de/group/hess/scratch/software/stable/cfitsio/sl6/cfitsio-3.340-gcc-4.8.1/lib/libcfitsio.so
#4  0x00007ffff730941c in ffbfwt ()
   from /afs/ifh.de/group/hess/scratch/software/stable/cfitsio/sl6/cfitsio-3.340-gcc-4.8.1/lib/libcfitsio.so
#5  0x00007ffff730a890 in ffflsh ()
   from /afs/ifh.de/group/hess/scratch/software/stable/cfitsio/sl6/cfitsio-3.340-gcc-4.8.1/lib/libcfitsio.so
#6  0x00007ffff7311968 in ffclos ()
   from /afs/ifh.de/group/hess/scratch/software/stable/cfitsio/sl6/cfitsio-3.340-gcc-4.8.1/lib/libcfitsio.so
#7  0x00007ffff7b3295a in GFits::free_members() () at GFits.cpp:1436
#8  0x00007ffff7b366cc in GFits::~GFits() () at GFits.cpp:142
#9  0x00007ffff7c63e55 in GCTAObservation::save(GFilename const&, bool const&) const () at src/GCTAObservation.cpp:1291
#10 0x000000000040d003 in ctobssim::run () at ctobssim.cpp:419
#11 0x00007ffff70e035a in gomp_thread_start () at ../../../gcc-4.8.1/libgomp/team.c:115
#12 0x0000003e8e407aa1 in start_thread () from /lib64/libpthread.so.0
#13 0x0000003e8d8e893d in clone () from /lib64/libc.so.6

I was just inspecting the last problem and found that the relevant line in the code is protected:

                #pragma omp critical(ctobssim_run)
                {
                    //obs_clone.save(outfile, clobber());
                    obs->save(outfile, clobber());
                }

Also for you first problem there is already a critical zone (although unnamed):

            #pragma omp critical
            {
            try {

                // Open FITS file
                GFits fits(m_filename);

                // Initialise events extension name
                std::string extname = fits.filename().extname("EVENTS");

                // Get event list HDU
                const GFitsTable& events = *fits.table(extname);

                // Load event data
                read_events(events);

                // Close FITS file
                fits.close();

            }
            catch (...) {
                has_exception = true;
            }
            }

Does the code that you are using have the same protection?

Yes, I have the same code compiled, I usually try to keep as close to devel as possible.

Also for you first problem there is already a critical zone (although unnamed):

Is the naming important?

Mayer Michael wrote:

Is the naming important?

Normally this is only needed to avoid conflicts between different OMP CRITICAL zones (remember, we had a deadlock situation during the last coding sprint).

This seems hence to be more related to the details of OpenMP. I would need do to a bit of more reading to understand what’s going on (did not find something evident on google). Maybe it’s related to calling the cfitsio library, which by default is not thread save (can however be compiled to be thread save).