| Symptom | Likely Cause | Fix | |---------|--------------|-----| | DLL not found | mkl_ccg.dll missing from PATH | Add MKL bin folder or copy DLL | | undefined reference to pd* | Forgot -lmkl_ccg | Add cluster library to linker line | | Segfault in pdgemm | MPI type mismatch | Recompile with same MPI as MKL | | Slow performance | Too many OpenMP threads per MPI rank | Set OMP_NUM_THREADS=1 or 2 initially | | MKL Cluster initialization failed | MPI not initialized before calling MKL | Call MPI_Init() first |
It is the Conjugate Gradient (CG) Solver component of the Intel MKL library. libmklccgdll work