How does MFIter work when a MultiFab has ghost cells

[ZiyangHuang]

Suppose I declare MFa a MultFab with 2 ghost cells. When I use:
for (MFIter mfi(MFa, TilingIfNotGPU()); mfi.isValid(); ++mfi)
{
const Box& bx = mfi.tilebox();

        amrex::ParallelFor(bx,
        [=] AMREX_GPU_DEVICE (int i, int j, int k)
        {
                ....
        });       

}

Are the ghost cells of MFa included in the above loop?

[WeiqunZhang]

No, the ghost cells are not included in the loop above. If you want to include ghost cells, you can use mfi.growntilebox(). By default, growntilebox includes ghost cells. You can also do growntilbox(1) if you only want one ghost cell. You can also do growntilebox(IntVect(0,1,0)) for zero ghost cells in x and z-directions and one ghost cell in y-direction.