[Trilinos-Users] Parallel Performance and non-continuous block layout

[M. Scot Breitenfeld]

  On 10/04/2010 11:54 AM, Heroux, Michael A wrote:
> Scot,
>
> The performance difference continuous and non-continuous should be minimal,
> for sufficiently large problems.
>
> Regarding your last questions, I think Alan Williams can best answer it.  I
> assume you are using the FECrsMatrix class, right?
Correct, I'm using FECrsMartrix.


> Mike
>
>
> On 10/4/10 11:29 AM, "M. Scot Breitenfeld"<brtnfld at uiuc.edu>  wrote:
>
>>    Does it effect the parallel performance to have non-continuous nodal
>> global ordering? For example, in 1D if I have (2 procs),
>>
>> 1    2    3   4    5   6   7   8
>> o    o   o   o  | o   o   o  o
>>
>> then the processors will have continuous blocks of rows (proc 0, 0-3:
>> proc 1: 4-7) or the other case:
>>
>> 1    4    5   8    3   6   7   2
>> o    o   o   o  | o   o   o  o
>>
>> where proc 0 has rows 0,3,4,7 and proc 1 has rows 2, 5, 7, 1.
>> Also, my method requires nodes in the region past partition boundary
>> (for example nodes 3,6,7 contribute to proc 0), not just the nodes
>> directly adjacent to the partition boundary.
>>
>> And another question, can I do my calculations for partition boundary
>> nodes (nodes involved with communication) and then: call
>> GlobalAssemble,  do the calculations for my interior nodes, and call
>> FillComplete ?
>>
>> Thanks,
>> Scot
>>
>>
>>
>>
>>
>> _______________________________________________
>> Trilinos-Users mailing list
>> Trilinos-Users at software.sandia.gov
>> http://software.sandia.gov/mailman/listinfo/trilinos-users
>
>