KSPCR with PCILU generally slower with v2.3.3 than with 2.3.0

[Etienne PERCHAT]

Hi Barry,

I don't understand why but -log_summary does not produce anything.
I've checked that the code has been compiled with DPETSC_USE_LOG.

Any tips ?
Thanks,

Etienne  

-----Message d'origine-----
De : owner-petsc-users at mcs.anl.gov [mailto:owner-petsc-users at mcs.anl.gov] De la part de Barry Smith
Envoyé : vendredi 6 juin 2008 16:39
À : petsc-users at mcs.anl.gov
Objet : Re: KSPCR with PCILU generally slower with v2.3.3 than with 2.3.0


   If you run both cases with -log_summary you'll see where it is  
spending more time.
Mail along the -log_summary output.

    Barry

On Jun 6, 2008, at 6:27 AM, Etienne PERCHAT wrote:

> Hi Barry,
>
> Using -ksp_truemonitor does not change anything. I have the same  
> number of iterations in the 3 cases (v2.3.3p8 + true_monitor,  
> v2.3.3, v2.3.0) and the same final residual norm but with v2.3.0 the  
> code is slightly faster.
>
> I have to stress that I also monitor convergence with KSPMonitorSet  
> in order to store the "best residual" and the "best solution" (I did  
> not test if it is still useful in 2.3.3).
>
> Etienne
>
> -----Message d'origine-----
> De : owner-petsc-users at mcs.anl.gov [mailto:owner-petsc-users at mcs.anl.gov 
> ] De la part de Barry Smith
> Envoyé : jeudi 5 juin 2008 20:28
> À : petsc-users at mcs.anl.gov
> Objet : Re: KSPCR with PCILU generally slower with v2.3.3 than with  
> 2.3.0
>
>
>    This could also be the result of changes in the way we test for
> convergence.
> Try with -ksp_truemonitor and see if it is using the same number of
> iterations
> to converge.
>
>    Barry
>
> On Jun 5, 2008, at 5:35 AM, Etienne PERCHAT wrote:
>
>> Hello,
>>
>> I'm solving MPIBAIJI matrices using KSPCR preconditioned by a
>> PCBJACOBI
>> between sub domains and PCILU with a fill ratio of 1 on each sub
>> domain.
>>
>> Solving exactly the same linear systems, I notice that the solution  
>> is
>> slower using v2.3.3p8 than with v2.3.0.
>> The behavior is not very clear: v2.3.3p8 is generally slower (10 % or
>> more) but on some systems it happen to be really faster (may be 40  
>> %).
>>
>> Unhappily in my case at the end I'm always slower ...
>>
>> Did somebody noticed such behavior? Is there changes if I upgrade to
>> current 2.3.3p13 version (I've seen a fix:" fix error with using
>> mpirowbs & icc & ksp_view") ?
>>
>> Thanks,
>> Etienne Perchat
>>
>>
>
>
>