[Trilinos-Users] BELOS GMRES

[Deepak Garg]

Hi,

I am using BELOS package of Trilinos (version 12.10.1) to solve my linear
system in parallel arising in finite element method. I use GMRES method
with ILU preconditioner following "BlockPrecGmresEpetraExFile.cpp" as an
example to write a wrapper class in my code. The matrix vector system in my
numerical problems are usually of size 1 million (entries in vector). The
entries in system vary from 0.00001 to 10000000.

I have three questions:

1. What should be the optimized values for the GMRES parameters such as
maxrestarts, maxiters and maxsubspace?

2. Is ILU preconditioner the best one to use with GMRES?  Are there other
preconditioners which can scale the system better than ILU?

3. Which is the fastest linear solver in BELOS package?

Kind regards,
Deepak
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://trilinos.org/pipermail/trilinos-users/attachments/20171206/64b48e4d/attachment-0001.html>