Hello, Does anyone here have experience with using Petsc on a Blue Gene system? I'm at IBM's Almaden Research Center and am currently involved in porting some code that uses Petsc to Blue Gene. I've managed to compile and run the code, and it seems to produce the correct results, but it generates many floating point alignment exceptions at runtime. I traced some of these warnings to a call to MatAssemblyBegin, so I'm thinking maybe the problem is in Petsc. The Blue Gene architecture requires 8- or 16-byte memory alignment for floating point operations, depending on whether they are issued in parallel, so I tried bumping up the alignment value in src/sys/src/memory/mal.c. This had no effect on the problem.
I didn't write any of the code I'm porting, and I'm not too familiar with it yet, so I suppose the problem could really be anywhere. My question here is simply this: has anyone seen this problem? Does it sound like an issue with Petsc, or is it more likely to be in the top-level code? Thanks, and best regards, Brian
