[Users] Problem with CarpetRegrid2/AMR

[Hal Finkel]

On Wed, 2011-08-31 at 13:53 -0500, Hal Finkel wrote:
> On Tue, 2011-08-30 at 21:06 -0400, Erik Schnetter wrote:
> > On Tue, Aug 30, 2011 at 5:28 PM, Hal Finkel <hfinkel at anl.gov> wrote:
> > > Could I also decrease the block size? I currently have
> > > CarpetRegrid2::adaptive_block_size = 4, could it be smaller than that?
> > > Is there a restriction based on the number of ghost points?
> > 
> > Yes, you can reduce the block size. I assume that both the regridding
> > operation and the time evolution will become slower if you do that,
> > because more blocks will have to be handled. This will also require
> > more memory, since each block carries its own ghost zone overhead.
> 
> When I try reducing the block size from 4 to 3, it exits with:
> 
> build/CarpetLib/th.cc:107: void th::regrid(): Assertion
> `times.at(ml).at(rl).at(tl) < times.at(ml).at(rl).at(tl-1)' failed.
> p0_31544:  p4_error: interrupt SIGx: 6

This happens with a larger box as well. It seems to have something to do
with setting: Carpet::refine_timestep = yes.

 -Hal

> 
> A block size of 2 is either really slow or it hangs.
> 
> I'll try a larger box for now.
> 
> Thanks again,
> Hal
> 
> > 
> > No, there is no such restriction.
> > 
> > -erik
> > 
> 

-- 
Hal Finkel
Postdoctoral Appointee
Leadership Computing Facility
Argonne National Laboratory
1-630-252-0023
hfinkel at anl.gov