Okay I will just experiment around with these then. Thanks for the input everyone
On Mon, Sep 21, 2015 at 6:21 AM, Mark Adams <[email protected]> wrote: > And I will just add that performance is sensitive to parameters. The > defaults try to be conservative and hypre's seem to be geared for 2D low > order discretizations. GAMG is probably a bit more geared for 3D. If you > are interested in looking this carefully you can run GAMG with '-info', and > grep on GAMG, and send us the results and we can verify that it running OK. > Also run with -log_summary and send that separately. The two solvers > should be about the same speed on your problem. > > > On Fri, Sep 18, 2015 at 7:36 AM, Jed Brown <[email protected]> wrote: > >> Justin Chang <[email protected]> writes: >> > I see that there's GAMG and there's Hypre's BoomerAMG (and perhaps >> others >> > too?) >> >> ML >> >> > What exactly is the difference between these two? Do they have very >> > different implementations under the hood? Does one have better >> > scalability over another? Or more importantly, when would I choose one >> > over the other? >> >> BoomerAMG is classical AMG, which is a different coarsening strategy >> From GAMG and ML which use smoothed aggregation. The math is different >> and the implementation is different. ML and GAMG have similar math and >> there exist configurations that are equivalent. >> > >
