matrix storage in LU-SSOR
 

Hey!

In the LU-SSOR implicit scheme, when solving the system (E+D+F)dU = -R, we execute several sweeps

(E+D)dU(k+1/2) = -R(n) - FdU(k)
(F+D)dU(k+1) = -R(n) - EdU(k+1/2)

If I understand correctly, the matrices E, D and F are typically computed at time step n.
My question: is it better to compute E, D and F at the beginning of the loop and store them (requires lots of memory, each matrix is actually a 5x5 matrix per cell), or recompute them at each iteration (waste of time...).

I thought that SSOR was supposed to be a low-memory scheme. How is this situation typically handled?

Thank you very much for your help!

Joachim