[julia-users] Unexpected performance drop when passing functions

2015-01-07 Thread Nils Gudat
I'm trying to understand the performance gains from supplying type information to functions. To this end, I've written a short piece of code https://github.com/nilshg/LearningModels/blob/master/test_argument_passing.jl that takes a vector x of the integers from 1:10 and multiplies it with

Re: [julia-users] Unexpected performance drop when passing functions

2015-01-07 Thread Mauro
The reason for the slowdown of case 4 is that Julia is not good at inferring the return types of functions passed as arguments to other functions. This shows up in a few places, for instance the `map` function has this problem too which I think has been partly hacked around. This is a bit of a

[julia-users] Unexpected performance drop when passing functions

2015-01-07 Thread Ivar Nesje
Yes, this is the current situation. Don't call functions in this way in a hot inner loop where you care about performance (yet). There are lots of things that can be done to improve this situation, but it hasn't reached the top of anyone's todo list yet. The best current workaround is to use a