[petsc-dev] PCASM: subdomains spanning multiple processes

[Barry Smith]

    We should have this for both ASM and block Jacobi. Not  
particularly difficult to write some code for it,

    BUT: the resulting morass of code would be nightmarish: three  
versions of ASM code for (1) one block per process, (2) several blocks  
per process (3) partial block per process, similar for block Jacobi.   
It would be good if we could have a single efficient code base for all  
the variants, but that may be difficult/impossible to design. We may  
just need to end up with a morass of code.

    Barry



On Apr 5, 2010, at 10:46 PM, Jed Brown wrote:

> Xiao-Chuan Cai asked about this today.  It seems to me that this would
> be possible without a huge amount of effort (building subcommunicators
> similar to PCRedundant), but it would take looking carefully at a fair
> amount of code.  Am I missing something that would make it especially
> hard?
>
> Jed