In[1]:= LaunchKernels[]
n = 1000;
Out[1]= {KernelObject[1, "local"], KernelObject[2, "local"]}
In[3]:= a = RandomReal[{}, {n, n}];
b = RandomReal[{}, {n, n}];
In[5]:= MapThread[Plus, {a, b}]; // AbsoluteTiming
Out[5]= {0.0270015, Null}
In[6]:= Parallelize[MapThread[Plus, {a, b}]]; // AbsoluteTiming
Out[6]= {0.3650209, Null}