[petsc-users] SNESVI convergence spped

[Ataollah Mesgarnejad]

Barry,

Here is my output from my program  with petsc-dev (txt files attached). Even with petsc-dev (revision 21929), SNES (I tried VISS and VIRS) takes a long time to converge (>50 iterations) from a small problem (99 HEX20 elements, 681 DOFs for SNES). The exodusII output files are uploaded in the link; I attached pictures of last time step for Psi field which we solve with SNESVI and u field which the displacement in the x-direction and is my loading.  As it was the case with petsc-3.2 line search diverges as soon as we hit the lower bound in a neighborhood of nodes. I ran with KSPPREONLY and PCLU to exclude possibility of LS failure because of the KSP tol.

Best,
Ata

link to exodusII files: http://cl.ly/0g431o443v240x1h2h1B

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