[petsc-users] PaStix is slower in pestc-dev

[Barry Smith]

  Looks like Pastix is running with different options hence different performance.

   Barry

On Dec 11, 2011, at 10:08 AM, Xiangdong Liang wrote:

> On Sun, Dec 11, 2011 at 9:04 AM, Matthew Knepley <knepley at gmail.com> wrote:
>> On Sun, Dec 11, 2011 at 12:05 AM, Xiangdong Liang <xdliang at gmail.com> wrote:
>>> 
>>> Hello PETSc team,
>>> 
>>> I was using PaStiX within petsc 3.1-p8. Today, I am trying PaStiX
>>> within petsc-dev. However, For the same code, solving the same linear
>>> system takes longer time (120s vs 90s) in petsc-dev. Both are compiled
>>> with debugging mode off. Is it possible that the newer PaStiX is
>>> slower than old version? or due to some options in compiling?
>> 
>> 
>> It is likely the options are not exactly the same, meaning the ordering is
>> different,
>> etc. Did you check everything wiht -ksp_view and -ksp_monitor?
> 
> I  use ksp_view, ksp_monitor options and same -pc_factor_zeropivot
> 1e-12, the dev version is still slower. One difference I see from
> pastix_verbose is the option of Pastix:
> 
> In pets-3.1: I have
> 
>      DISTRIBUTED         :                  Not defined
>       FLUIDBOX            :                  Not defined
>       METIS               :                  Not defined
> 
> 
> While in petsc-dev, I have
> 
>      DISTRIBUTED         :                   Defined
>        METIS               :                   Not defined
>        WITH_SCOTCH         :                   Defined
> 
> 
> However, I do not understand these options. Could that be the reason?
> 
> Xiangdong
> 
>> 
>>    Matt
>> 
>>> 
>>> Best,
>>> Xiangdong
>>> 
>>> PS. I cannot use PaStiX in 3.2 because in the runtime, PaStiX crashed
>>> due to missing of the option -DWITHSCOTCH during compiling. It was
>>> reported before by one user and fixed in petsc-dev, but not in
>>> petsc-3.2-p5.
>>> 
>>> http://lists.mcs.anl.gov/pipermail/petsc-users/2011-March/008356.html
>> 
>> 
>> 
>> 
>> --
>> 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