Terrible run time with Parallel computin

Terrible run time with Parallel computin

I have use this code for running two function simultaneously. but run time
is Terrible.my CPU is dual core and function g and g1 do not interact.in
normal run xc1 is matrix with 4950 row and 4 column and same for xc2.
matlabpool ('open',2);
parfor i = 1:2
if i == 1
xc1=gh(0.10001,0.8,12,0.2,68,1.2);
else
xc2=gh1(3,0.40001,9,0.7,50,3.25);
end
end
matlabpool close;