As I think I said earlier: ILU will behave differently with BAIJ and AIJ 
format. With BAIJ it uses a point block factorization (doing an ILU treating 
each block in the matrix as a single point (and doing a dense factorization for 
the inverse) while AIJ ignores the block size and just uses a point ILU. So in 
general the convergence with BAIJ vs AIJ and ILU will be different; usually 
BAIJ will converge better but it need not.

   Barry

> On Mar 18, 2015, at 1:23 PM, Chung-Kan Huang <[email protected]> wrote:
> 
> Sorry I didn't state my problem more accurate.  The entries in the input 
> matrixes and vectors​ are correct -- they have right values and correct 
> nonzero structure.
> The KSP was setup so I can solve the lienar systems for an unsteady state 
> convective problem.
> I use KSPBCGS + PCILU and so far I only try sequential on a very small 
> problem.
> I wonder if blocked ilu is actually used in  MATBAIJ2MATAIJ case.
>  
> Thanks,
>  
>  

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