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reusing factorization when solving multiple problems in parallel

+4 votes

Hi, I am solving several problems simultaneously in parallel, similar to the question:

http://fenicsproject.org/qa/6089/solve-problems-parallelly-with-fenics-which-relative-with

Is it possible to reuse a factorization in parallel? Consider the code:

solver = LUSolver()
solver.set_operator(A)
solver.parameters["reuse_factorization"] = True

This obviously works when using one processor, however when using multiple processors the factorization is computed at each rank. So if I do not have as many processors as problems that I wish to solve then I will basically have to wait for the additional factorizations to be computed.

Alternatively: Does anyone know what pack is used for computing the factorization, such that I might use that for equally efficient LU factorization and then transfer the L and U matrices.

asked Mar 3, 2015 by hgar FEniCS Novice (770 points)
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