DH_generate_key( ) Vs DH_compute_key( )

[ikuzar]

Hello,
I'd like to know if DH_compute_key( ) runs faster than DH_generate_key( ).
DH_generate_key generate x and g^x, in my case ( x was not set when I call
this function ).
I only made measure for DH_generate_key and have got 0.00 ms ( CPU Intel
Core i7-740QM, 1.73Ghz / 6GB of memory ). Is it normal ... ?
Thanks for your help.