I followed the example: https://gist.github.com/andr3wmac/78d294844484cb48342f88ef03e2776a
The matrix is "nd6k: https://www.cise.ufl.edu/research/sparse/MM/ND/nd6k.tar.gz"
The program is finished regularly, but the summary shows that GPU is not called.
The summary is:
CHOLMOD GPU/CPU statistics:
SYRK CPU calls 799 time 3.7243e+00
GPU calls 0 time 0.0000e+00
GEMM CPU calls 628 time 2.0252e+00
GPU calls 0 time 0.0000e+00
POTRF CPU calls 172 time 2.9389e+00
GPU calls 0 time 0.0000e+00
TRSM CPU calls 171 time 1.1470e+00
GPU calls 0 time 0.0000e+00