From my reading of the SuiteSparse: In order to use one of the direct solvers, the CSC sparse matrix is converted to an internal type, `Sparse`

. Unfortunately, at that point the memory used for the matrix is duplicated because SuiteSparse uses its internal storage to operate on the matrix.

If this is true, it really becomes a prohibiting factor when dealing with large systems of coupled linear algebraic equations. What is the solution? I don’t know, but I suspect that a true Julia-only solver would need to be written.