[petsc-users] Questions about ASM in petsc4py

[Jed Brown]

Chih-Hao Chen <chih-hao.chen2 at mail.mcgill.ca> writes:

> Hello Matt,
>
>
> Thanks for the information.
> After using -log_summary to print out for both cases, I found both of them(openMpi and Mvapich2) give same performance.
>
> On the other hand, I still cannot get clear ideas how to get the returned subKsps by the function of  getASMSubKSP.
> It seems the return subKsp are saved in a list of KSP objects.
> So I used :
>
> subksp = pc.getASMSubKsp()
> subksp[0].setType(‘richardson')
> subksp[1].setType(‘richardson’)
>
> with 2 processors.
> But it showed "list index out of range”.

If you do ASM with one subdomain per process, then of course only
subksp[0] is valid.  ASM can also be run with multiple subdomains per
process, it just isn't the default.

> As you said on each rank, I can get the local KSPs.
> Would you mind telling me how to get them?

You got them.
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 818 bytes
Desc: not available
URL: <http://lists.mcs.anl.gov/pipermail/petsc-users/attachments/20160316/ade3852a/attachment.pgp>