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Comment by nwvg_7257 | Hacker News Reader

I would encourage you to try this again on Julia 1.8. Startup time has improved a lot. A few minutes seems way too long to process some images. Even plotting should happen within 20-30s now.

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Possibly related recent discussion: https://news.ycombinator.com/item?id=35106488

Will try! The image warping was done by an external program. Julia was used just to multiply two matrices of size 3x3 for each image in the collection. Launching the interpreter took almost a whole second, the rest of the computation was instantaneous.

Did you launch Julia for each image separately?

Yes. I was using julia as a shell calculator to multiply small matrices. Octave happens to be much faster for this (admittedly niche) use case.

Working this way is pretty common for small tasks. As has been suggested, Julia 1.9 is a lot faster than it was before. I find it's more like 4 seconds than 0.5 seconds, though.

With plot.jl as

    $ cat plot.jl
    using Plots
    x = range(0, 10, length=100)
    y = sin.(x)
    plot(x, y)

I find that

    $ time julia plot.jl

yields

    4.19s user 0.50s system 106% cpu 4.409 total

Plotting is a complicated beast. If you just want to multiply matrices, there's no "using" statement and you get sub-second running times. Still geologically slow, but at least somewhat manageable.

Startup time for plots is down to <0.5s with Julia 1.9 (in beta).

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