Time a function multiple times to see how memory usage behaves.

time_lm.jl

import Base: gc_bytes, gc_time_ns, time_print

function lm_1_10(x1, x10)
    A = (x10-x1)/9
    B = (10*x1-x10)/9
    A,B
end

macro time_N(N, ex)
    quote
        local b0 = gc_bytes()
        local t0 = time_ns()
        local g0 = gc_time_ns()
        for i=1:$(esc(N))
            $(esc(ex))
        end
        local g1 = gc_time_ns()
        local t1 = time_ns()
        local b1 = gc_bytes()
        t1-t0, b1-b0, g1-g0
    end
end

macro time_lm(ex)
    quote
        local val = $(esc(ex))
        dt1, db1, dg1 = @time_N 1 $(esc(ex))
        dt10, db10, dg10 = @time_N 10 $(esc(ex))
        tA,tB = lm_1_10(dt1, dt10)
        bA,bB = lm_1_10(db1, db10)
        @printf "resources: %.2e*N + %.2e sec (%d * N + %d bytes)\n" tA/1e9 tB/1e9 bA bB
        val
    end
end