[Rivet] Jimmy stops with CODE 300

[Andy Buckley]

On 27/05/10 11:00, Jonathan Butterworth wrote:
> Hiya,
> 
> Andy Buckley wrote:
> 
>> Got to event 78887, with the .3 JIMMY build, before getting the fatal
>> 300 message and abort. Damn, some more digging required...
> 
> Mmm. So this looks like you reduced the problem but didn't elimiate it?
> It might be that running in this minbias mode with this tune,
> herwig+jimmy actually (rarely?) exceeds 10000 particles? If the fortran
> herwig and jimmy is compiled without bounds checks this could have
> unpredictable results.
> 
> (of course good fortran should protect against such things and herwig
> and jimmy may do but I am not 100% sure).
> 
> If I had a working set up now with herwig and jimmy compiled myself, I
> would insert write statements in to see what NHEP and MAXER are at the
> end of each event...

Think I've got it: despite trying to linking against the ".3" builds,
the NMXHEP size was always 4000! Digging a bit, it turns out that we
were relying on Genser's symlink to Herwig with the version name being a
variant of "6510", i.e. "6510.3" in
/afs/cern.ch/sw/lcg/external/MCGenerators/herwig/... but these symlinks
hadn't been updated for the builds with larger HEPEVT. So JIMMY was
expecting NMXHEP = 10000 but we were accidentally getting a HERWIG with
NMXHEP = 4000.

I've changed some bits of the generator loader so that we don't get the
wrong symlink any more, when using Genser's builds. For private biulds
of the generators, make sure you are using the ".3" tarballs of both
HERWIG and JIMMY. Note that the change in the loader means that the
command-line name for HERWIG now ends in "6.510" rather than "6510".

Holger, can you try this out? Hopefully problem solved, but you might
well need to rebuild your local versions of HW and JIMMY from the Genser
".3" tarballs.

Andy

-- 
Dr Andy Buckley
SUPA Advanced Research Fellow
Particle Physics Experiment Group, University of Edinburgh

The University of Edinburgh is a charitable body, registered in
Scotland, with registration number SC005336.