[gmx-users] Segmentation Violation

[David van der Spoel]

On Thu, 2003-03-13 at 15:54, James O'Dell wrote:
> I have not done detailed scaling tests yet but I have tried on
> 2,4,6,8... and it seems to get segmentation violations on anything
> greater that 8 processors.
> 
> A stack trace from the debugger seems to indicate that MPI signaled
> the error. Could it be that there is simply so much communication
> traffic that MPI's internal buffers simply overflowed?
> 
Could it be the problem recently noted on the list that you have no
water on the first processor anymore? Is it the first processor that
crashes actually?


> Jim
> 
> 
> On Wed, 2003-03-12 at 12:34, Anton Feenstra wrote:
> > James O'Dell wrote:
> > > I have a simulation that I can run on a single processor or on an 16
> > > processor cluster. The simulation seems to run just fine on the single
> > > processor. ON the 16 processor cluster, it gets a segmentation fault
> > > almost immediately after loading. I'd appreciate any pointers on how to
> > > debug this.
> > 
> > Try it stepwise, i.e. first try a single processor run on your cluster,
> > then 2, 4, 8. (While you're at it, you can also keep track of wallclock
> > times used so you get an idea of the scaling.)
> > 
> _______________________________________________
> gmx-users mailing list
> gmx-users at gromacs.org
> http://www.gromacs.org/mailman/listinfo/gmx-users
> Please don't post (un)subscribe requests to the list. Use the 
> www interface or send it to gmx-users-request at gromacs.org.
> 
-- 
Groeten, David.
________________________________________________________________________
Dr. David van der Spoel, 	Dept. of Cell & Mol. Biology
Husargatan 3, Box 596,  	75124 Uppsala, Sweden
phone:	46 18 471 4205		fax: 46 18 511 755
spoel at xray.bmc.uu.se	spoel at gromacs.org   http://xray.bmc.uu.se/~spoel
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++