Julia: @time a set of functions

Question

I have a script.jl which looks more or less like this:

...

function main()
    a::... = function1()
    b::... = function2(...)
    c::... = function3(...)
    A::... = function4(...)
    B::... = function5(...)
    C::... = function6(...)
end

main()

I cannot @time main() because functions 1-3 are input functions and therefore their execution times depend on how fast or slow the user is. Is there a way to time only function 4-6? I don't know, something like this:

...

function main()
    a::... = function1()
    b::... = function2(...)
    c::... = function3(...)
    @time(
    A::... = function4(...)
    B::... = function5(...)
    C::... = function6(...)
    )
end

main()

Answer 1

Note: I guess this is just an example but the syntax C::... is not valid Julia syntax, it's better if you provide simple but functional examples.

You can prepend each expression that you are interested in timing with a @time macro annotation if you want independent timings:

function main()
    a = function1()
    b = function2(...)
    c = function3(...)
    @time A = function4(...)
    @time B = function5(...)
    @time C = function6(...)
end

main()

or:

function main()
    a = function1()
    b = function2(...)
    c = function3(...)
    @time begin
        A = function4(...)
        B = function5(...)
        C = function6(...)
    end
end

main()

This is similar to @Gomiero answer, just that in order to time several functions with the @time macro you need to introduce a new block and stuff everything in there.

Also checkout the still unregistered packageBenchmarks, ie:

julia> Pkg.add("https://github.com/johnmyleswhite/Benchmarks.jl.git")

julia> using Benchmarks

julia> function test()
           x = 0
           for i in 1:1000_000_000
               x += 1
           end
           return x
       end
test (generic function with 1 method)

julia> @time test()    # JIT warmup!
  0.003669 seconds (1.71 k allocations: 90.799 KB)
1000000000

julia> @time test()
  0.000002 seconds (5 allocations: 176 bytes)
1000000000

julia> @benchmark test()
================ Benchmark Results ========================
     Time per evaluation: 6.03 ns [5.92 ns, 6.13 ns]
Proportion of time in GC: 0.00% [0.00%, 0.00%]
        Memory allocated: 0.00 bytes
   Number of allocations: 0 allocations
       Number of samples: 6301
   Number of evaluations: 811601
         R² of OLS model: 0.951
 Time spent benchmarking: 2.96 s

If you want to time several expressions use the begin block approach.