Poor performance of mkl_sparse_spmm

[charlesqhappy]

I use mkl_sparse_spmm on two 80 *80 matrix, I run the function in a loop. The time cost is at 10e-5 seconds level in most cases, but very often,  it  can up to be 0.1+ second.

Why it suddenly slow? Should I always use mkl_sparse_set_mm_hint before mkl_sparse_spmm ?

[Gennady_F_Intel]

I don't think if mkl_sparse_set_mm_hint will help. I think it is OS related problems. Is that windows os?

[charlesqhappy]

Yeah, I'm using windows. And Unity and C++ dll in Unity. The mkl code is in c++ dll.

Very strange, what could happen when the single function slow down? I just do a multiplication.