[FLASH-USERS] Flash crashes when corenumber!=2^n

[Klaus Weide]

On Tue, 28 Feb 2012, Hunger, Lars wrote:

> Hi Klaus,
> 
> I reexamined the problem and realized that ,on my system , it works not only on 2^n cores.
> It does always run on 2,4,6,8,16,32,64 cores.
> I cannot get it to run on 5,6,7,9,10,11,12,13,14,15,96,112,120 cores.
> A curious case presents itself when I try to run the Sedov problem with 3 cores: Then it works around and sometimes not.

Lars,

I have tried to reproduced your problem with Sedov in FLASH3.3, but have 
not been able to.  I suspect that your problem has something to do with
your MPI implementation, or possibly with the way your MPI library has 
been compiled or with compiler flags used for compiling the FLASH code.

I suggest you try one or more the following:

 1. Try to compile and run on a different system, if possible.
 2. Try to use a different MPI implementation - mpich2 instead of openmpi,
    or at least a different version.
 3. Compile without optimization (i.e., without -mtune=native and without -O2).
    Depending on yoru Makefile.h, it may suffice to add -debug to the 
    setup command.
 4. Use Paramesh4dev instead of Paramesh4.0 (setup shortcut +pm4dev).
    (Paramesh4dev is closer to the latest released PARAMESH code.)
 5. Use the latest FLASH release, FLASH4-beta. (This is recommended 
    anyway!)

Let us know if any of this solves your problem!

If further debugging is necessary, you should definitely do 4 & 5.


Klaus