Barry:

There might be bugs in the implementation. On the other hand when it is a user 
defined Vec as in SAMRAI it is unclear how you 
would/could make it more error-proof within changing some of the present 
structure.

Bobby

On Jun 6, 2011, at 3:55 PM, Barry Smith wrote:

> 
> On Jun 6, 2011, at 2:50 PM, Boyce Griffith wrote:
> 
>> I maintain similar SAMRAI-PETSc stuff, although I'm only synched up with 
>> PETSc 3.1, not petsc-dev.  VecNorm caching caused me endless grief until I 
>> started making lots of calls to PetscObjectStateIncrease(), both in the Vec 
>> routines and in the Mat/nonlinear function wrappers.
>> 
>> If you are "building your own" Vec class, is there a better/safer way to 
>> ensure that cached Vec data is properly invalidated?
> 
>   Hmm, in theory the "base" vector class that calls your implementation is 
> suppose to manage the cache/state stuff, for example VecAXPY() updates the 
> state of the y vector. So this should not be problem except in nonlinear 
> function evaluates where YOU are changing the vector entries directly and 
> need to update the state.  Of course, there could be bugs in some of our base 
> Vec classes, please report any you know about and we'll get them fixed.
> 
>   Barry
> 
> 
> 
>> 
>> -- Boyce
>> 
>> On 6/6/11 3:40 PM, Bobby Philip wrote:
>>> What usually breaks for me is VecNorm caching, arguments for functions,
>>> and introduction of new functions. Once in a while the PETScObject structure
>>> changes and that causes trouble too. But this is my usual list.
>>> 
>>> Any time petsc-dev changes, I end up having to build:
>>> 
>>> 1. SAMRAI
>>> 2. SAMRUtils
>>> 3. SAMRSolvers
>>> 4. PFLOTRAN
>>> 
>>> with stops along the way to fix anything that broke mainly in 1 and 4. 
>>> Also, SAMRAI
>>> continues to only want to support version 2.3.3 of PETSc so I end up 
>>> keeping tabs
>>> on what needs to be changed with each new SAMRAI version. A set of automated
>>> tests I hope might be the right catalyst to move them to the present 
>>> generation(s) of PETSc.
>>> 
>>> Bobby
>>> 
>>> On Jun 4, 2011, at 9:09 AM, Matthew Knepley wrote:
>>> 
>>>> On Sat, Jun 4, 2011 at 8:03 AM, Bobby Philip<philipb at ornl.gov>  wrote:
>>>> 
>>>>> Barry:
>>>>> 
>>>>> I heartily agree with all that you have said. Thanks for your suggestions.
>>>>> I do believe what you have suggested is the best both in the shorter and
>>>>> longer term. As a clarification on freezing the petsc-dev version, my
>>>>> suggestion was to freeze
>>>>> the version for a few months at a time as it reduces the burden on me on
>>>>> fixing frequent breakages.
>>>>> 
>>>> 
>>>> We don't have to bog down pflotran-dev with particulars, but can you
>>>> characterize what breaks
>>>> most often for you, or what you find yourself doing most often for SAMRAI?
>>>> 
>>>> Thanks,
>>>> 
>>>>    Matt
>>>> 
>>>> 
>>>>> Regards,
>>>>> Bobby
>>>>> 
>>>>> 
>>>>>> 
>>>>>> Peter,
>>>>>> 
>>>>>>  In the mid to longer term we need to make sure that SAMRAI has more
>>>>> resources than a one man operation, so this is something that needs 
>>>>> coverage
>>>>> in the next round of SciDAC.
>>>>>> 
>>>>>>  When dealing with tracking package changes I've found the best way is
>>>>> to track them continuously so each new issue (due to a change) gets fixed
>>>>> immediately rather than waiting until a bunch of stuff is broken before
>>>>> fixing it.  This way determining what change broke what, is much easier.
>>>>> This means we should set up nightly tests of PETSc+SAMRAI+PFLOTRAN and 
>>>>> deal
>>>>> with each issue the day after it breaks instead of weeks later. Probably
>>>>> Richard could set up such a test and have it send email to say Richard,
>>>>> Bobby and I each time a breakage occurs.
>>>>>> 
>>>>>> 
>>>>>> Barry
>>>>>> 
>>>>>> 
>>>>>> 
>>>>>> 
>>>>>> 
>>>>>> On Jun 3, 2011, at 5:49 PM, Lichtner, Peter C wrote:
>>>>>> 
>>>>>>> Folks: we have a problem trying to integrate PFLOTRAN with PETSc and
>>>>> SAMRAI. The basic problem is that when PETSc is updated it often breaks
>>>>> SAMRAI in nontrivial ways. For PFLOTRAN itself the changes needed are
>>>>> usually minor to bring PFLOTRAN back in sync with PETSc. But this is not 
>>>>> the
>>>>> case for SAMRAI. Bobby Philip, the lead on SAMRAI, does not have the
>>>>> resources to develop the PFLOTRAN implementation of SAMRAI and keep it up 
>>>>> to
>>>>> date with changes in PETSc. The question is how to resolve this 
>>>>> difficulty.
>>>>> We have expended a considerable effort in adding SAMRAI to PFLOTRAN and
>>>>> several directions of PFLOTRAN development rely on SAMRAI including
>>>>> applications to CO2 sequestration, the Hanford uranium plume, and a hybrid
>>>>> model using the lattice Boltzmann method at the pore scale coupled to the
>>>>> Darcy continuum scale with SAMRAI providing the bridge between the two
>>>>> scales. Bobby has suggested freezing the PETSc developer version used in
>>>>> PFLOTRAN. However, this would potentially limit the development of 
>>>>> PFLOTRAN.
>>>>> An alternative approach is to create a separate branch of PFLOTRAN for use
>>>>> with SAMRAI. However, this would limit our ability to develop a hybrid
>>>>> model, not to mention causing difficulties down the road when the two
>>>>> branches are finally merged. Any thoughts, suggestions, comments, etc.
>>>>> appreciated on how we can best resolve this issue.
>>>>>>> Thanks, ...Peter
>>>>>>> <><><><><><><><><><><><><><><><><><><><><>
>>>>>>> Peter C. Lichtner (lichtner at lanl.gov)
>>>>>>> LANL EES-16: MS D469
>>>>>>> (505) 667-3420 (o), 665-3285 (fax), 795-2881 (cell)
>>>>>>> Los Alamos National Laboratory
>>>>>>> SM-30 Bikini Atoll Road
>>>>>>> Los Alamos, NM 87545
>>>>>>> blockedblockedblockedhttp://www.ees.lanl.gov/pflotran/
>>>>>>> <><><><><><><><><><><><><><><><><><><><><>
>>>>>>> 
>>>>>>> 
>>>>>>> 
>>>>>> 
>>>>>> 
>>>>> 
>>>>> 
>>>> 
>>>> 
>>>> --
>>>> What most experimenters take for granted before they begin their 
>>>> experiments
>>>> is infinitely more interesting than any results to which their experiments
>>>> lead.
>>>> -- Norbert Wiener
>>> 
>>> 
> 
> 


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