[petsc-dev] Monitor changes

[Barry Smith]

On Aug 14, 2011, at 12:15 PM, Jed Brown wrote:

> On Sun, Aug 14, 2011 at 12:05, Barry Smith <bsmith at mcs.anl.gov> wrote:
>   Well, you are argeeing with me. Publishing an object with AMS is different than viewing them and so AMS publishing is not a subclass of PetscViewer it is a separate thing.
> 
> 1. I thought AMS was normally allowed to look at it later (because it returned a memory reference).

   Yes, the publisher is required to insure that all memory references that they publish as fields remain around as long as the AMS memory exists. 

> By what mechanism does AMS become synchronous (because it must if you publish a stack variable which will only be valid instantaneously).

   It doesn't, you don't publish stuff on the stack.  There is no such concept.


> 
> 2. We could create an "AMS" viewer that, instead of actually reading the published values with a separate process, printed it (or wrote to a file).

   Yes

> 
> I need to go use AMS for something so that I can have an intelligent discussion about its implementation/capability.
>  
>   You mean "change the AMS API"? Godzooks you are asking too much :-(  Reason, this information has to be propagated through all the AMS code which scares me too much to consider.
> 
> Alternative rationale: AMS does not have a big network of dependencies yet so now is the best time to make it just how we eventually want it. Getting hands dirty in AMS (although this may be a somewhat superficial change) would be useful for me anyway.

  Valid point. Before doing that I think we need to toughen up the test suite a bit, the tests are a bit too much like  "examples" and not enough "automatic tests".

   Barry