On 09/13/2012 05:12 PM, Paul T. Bauman wrote: > On Thu, Sep 13, 2012 at 4:06 PM, David Knezevic > <[email protected] <mailto:[email protected]>> wrote: > > On a related issue, I wanted to mention 3D linear elasticity example > that I added: systems_of_equations_ex6. It seems very slow with the > default iterative solver in PETSc (ILU + GMRES, right?). The example > takes 26 seconds on my laptop. > > But this is a symmetric problem, so you'd expect CG to be good. > > > Yes, in another lifetime when I was doing nonlinear elasticity, CG was > quite good. > > Calling > ./systems_of_equations_ex6-opt -ksp_type cg > runs fast, but gives the wrong answer > > > That's alarming... > > Is ICC the default preconditioner with CG? If not, give that a try > (maybe with -pc_factor_levels 4 or something)
ahh, "-pc_type icc" did the trick, thanks! I'll add that to the Makefile. David ------------------------------------------------------------------------------ Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ _______________________________________________ Libmesh-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/libmesh-users
