[petsc-users] EPS performance

[Jose E. Roman]

El 20/04/2015, a las 17:09, siddhesh godbole escribió:

> hello 
> 
> i am trying to solve generalized eigenvalue problem using eps solver. i have a monte carlo loop in the program which has to run for about 1000 times. matrix sizes are 15 X 15 as a dummy problem and 23040 X23040 in the real problem.
> as i run the program i see that eps takes increasingly more amount of time for computation with respect to iterations and number of processors too.
> i have used all the options to the best of  my knowledge and need your help to improve the program in any way possible.
> i am attaching .c file of mycode with this email. 
> 
> I would be extremely greatful to you for your valuable suggestions.
> 
> 
> 
> Siddhesh M Godbole
> 
> 5th year Dual Degree,
> Civil Eng & Applied Mech.
> IIT Madras
> <mycode.c>

For the large problem, you should consider doing preallocation of matrices.

A generalized eigenproblem needs a linear solver. By default EPS uses a sequential direct solver, see FAQ#6 http://slepc.upv.es/documentation/faq.htm and section 3.4.1 of the users manual. In the development version, we have changed this so that the user gets a run-time error when trying to use a sequential direct linear solver in parallel runs.

Jose