Gadget2 fatal error

From: Cameron McBride <cameron_at_phyast.pitt.edu>
Date: Tue, 16 Oct 2007 19:37:41 +0000

Greetings,

We ran into the following error while trying to benchmark and test
Gadget2 for some DM only simulations on a Cray XT3 platform.

--
domain decomposition...
aborting job:
Fatal error in MPI_Allgatherv: Invalid buffer pointer, error stack:
MPI_Allgatherv(1022): MPI_Allgatherv(sbuf=0xf8ab6b0, scount=1931904,
MPI_BYTE, rbuf=(nil), rcounts=0xfac6750, displs=0xfac7760, MPI_BYTE,
MPI_COMM_WORLD) failed
MPI_Allgatherv(966): Null buffer pointer
--
We are using PMGRID=2048 on 1024 PE, and the simulation consists of
1250^3 particles.  With the same Gadget2 binary on the same number of PE, we were able to run smaller simulations (640^3 and 960^3).
Initially, we hit a very similar error on any attempt to use 1024 PE.
We were able to get around this by changing the TOPNODEFACTOR to '2.0'
from the original value of '20.0' in the domain.c file and we got the
960^3 particle simulation to run.  Changing this back to '20.0' did not
fix the issue for the 1250^3 run.
The version of Gadget2 we're using is pretty much a stock 2.0.3 version.
Any ideas?  Thanks!
Cameron  

Received on 2007-10-16 21:38:41