When I run the following code:
I = 1000; J = 1000; K = 1000; A = rand(I,K); B = rand(K,J); C = zeros(I,J); ticfor i=1:I for j=1:J for k=1:K C(i,j) = C(i,j)+A(i,k)*B(k,j); end endendtoc
it takes 7.7 seconds on R2015a and 26.1 seconds on R2015b, which is over a 3 times slowdown. I've emailed support, but they cannot determine why it runs slower, only that the new JIT should speed up code on average. However, this code seems very simple and I'd like to better understand when the new JIT will increase performance vs degrade performance. Thanks for any help.
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