I have also found that Trilinos is about 4x faster for a 200x50 domain. Also, in a for some problems where the standard solver gives bad results, the Trilinos solvers give accurate results. I believe these are "stiff" problems, but I haven't actually looked at the matrix.
While it doesn't help for solving large domains, you can gain speed increases on multi-core machines for embarrassingly parallel problems (i.e., multiple separate cases) using IPython. Best Regards, Angus Hendrick On Wed, Apr 1, 2009 at 6:18 AM, Jonathan Guyer <[email protected]> wrote: > > > On Apr 1, 2009, at 3:28 AM, Sum Thai Wong wrote: > > I was trying to run some rough benchmarks to compare the speedup using >> Trilinos. To my surprise, Fipy actually runs faster without Trilinos, and by >> a significant margin. Could this be possible? >> > > Possible and probable. If you look at the results for "sandbox" at > http://matforge.org/fipy/build/trunk you can see that we get the same > thing (sandbox is the only test slave that's properly configured for > Trilinos at the moment). > > The test suite is not actually of much value for benchmarking. It's running > through a lot of very small problems, so the overhead in both memory and > speed is substantial. It doesn't surprise me that the overhead for using > Trilinos is even worse. > > I am presently working on setting up a benchmarking script for our own > ongoing diagnostics. I'll post when I have the results up. > > > I notice that only a single core is being utilised? >> > > Correct. Presently, the only advantage of using Trilinos with FiPy is that > has a much richer suite of preconditioners and, under some circumstances, > can solve the matrix in parallel to some advantage. Because FiPy can only > presently *build* the matrix in serial, this really comes down to a > case-by-case situation. Dan Wheeler is more experienced with this, but I > think he's out for a few days. > > > We are working on a couple of routes to parallelizing the whole process and > will post here when we have something available. > > > Thanks for your interest and let us know how we can further help. > >
