-users@mcs.anl.gov
Subject: Re: [petsc-users] FGMRES and BCGS
It is not surprising. BCGS uses less memory for the Krylov vectors, but that
might be a small fraction of the total memory used (considering your matrix and
GAMG). FGMRES(30) needs 60 work vectors (2 per iteration). If you're using a
linea
It is not surprising. BCGS uses less memory for the Krylov vectors, but that
might be a small fraction of the total memory used (considering your matrix and
GAMG). FGMRES(30) needs 60 work vectors (2 per iteration). If you're using a
linear (non-iterative) preconditioner, then you don't need a
Good Morning,
I usually solve a non-symmetric discretization of the Poisson equation using
GAMG+FGMRES.
In the last days I tried to use BCGS in place of FGMRES, still using GAMG as
preconditioner.
No problem in finding the solution but I'm experiencing something I didn't
expect.
The test case
