[petsc-users] EPSSolve in a loop

[Dharmendar Reddy]

Hello,
          I see an interesting behavior when i call EPSSolve in a loop. Can
you help me figure out whats going on ?

I have a setup like this to solve a A x = lambda B x   (Generalized
Hermitian problem)

type eigenSolver_t
  EPS :: eps

end type eigenSolver_t

the type has bound procedure which calls  EPSSetOperators and EPSSolve when
eigenSolver%solve() is called

Now i run a for loop

do ic=1,111
  call eigenSolver(ic)%solve()
end do

I print the time for each solve.  The operators A,B =A1,B1 for ic=1 to 50
A2,B2 for ic=51 to 80  and A3,B3 for ic=81 to 111

Now i see that time per solve per ic is almost constant when i use
-eps_type lapack.
But for, defualt solver, time per solve seem to increase with increasing
ic. Have look at the attached timing information.

Also, Time per solve using lapack is lower than any of the iterative
solvers i have tried. Problem size is about 100 x 100, operators are
tri-diagonal.


Thanks
Reddy
-- 
-----------------------------------------------------
Dharmendar Reddy Palle
Graduate Student
Microelectronics Research center,
University of Texas at Austin,
10100 Burnet Road, Bldg. 160
MER 2.608F, TX 78758-4445
e-mail: dharmareddy84 at gmail.com
Phone: +1-512-350-9082
United States of America.
Homepage: https://webspace.utexas.edu/~dpr342
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