This list of solvers that have worked fairly consistently, try them out locally and if the recovery solver is not activated, you should be safe for longer transient runs:

{{{
#!m
% biconjugate gradient with block Jacobi preconditioner [Thiago's favorite]
md.toolkits.DefaultAnalysis=bcgslbjacobioptions();
}}}

{{{
#!m
% gnres with block jacobi preconditioner [Martin's favorite]
md.toolkits.DefaultAnalysis=gmresbjacobioptions();
md.toolkits.DefaultAnalysis.ksp_max_it=1;
}}}
{{{
#!m
% ASM, used for mass conservation but may work for other things
md.toolkits.DefaultAnalysis=asmoptions();
}}}
{{{
#!m
% An iterative solver may work for one analysis and not another, you can assign a solver to each, like this:
md.toolkits.StressbalanceAnalysis = gmresbjacobioptions();
md.toolkits.DefaultAnalysis=issmmumpssolver();
}}}

Make sure to always keep MUMPS as the recovery solver (it is slow but extremely robust):
{{{
#!m
%Keep recovery mode as MUMPS
md.toolkits.RecoveryAnalysis=issmmumpssolver();
}}}