# REPL Speed in Juno/JuliaPro vs Julia REPL

**URL:** <https://discourse.julialang.org/t/repl-speed-in-juno-juliapro-vs-julia-repl/48749>\
**Category:** New to Julia\
**Created:** [October 21, 2020, 2:08pm UTC](https://discourse.julialang.org/t/repl-speed-in-juno-juliapro-vs-julia-repl/48749 "2020-10-21T14:08:27Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![jdietl](https://avatars.discourse-cdn.com/v4/letter/j/df788c/32.png) [@jdietl](https://discourse.julialang.org/u/jdietl)\
**Post date:** [October 21, 2020, 2:08pm UTC](https://discourse.julialang.org/t/repl-speed-in-juno-juliapro-vs-julia-repl/48749/1 "2020-10-21T14:08:27Z")

</div>

Hi. I’m a new user and I’m working through the JuliaAcademy data science tutorial (except I’m trying to run the examples in JuliaPro instead of the notebooks because I don’t like notebooks very much).

I have a question about the REPL in Juno. It seems to be very sluggish, especially compared to the REPL when I just load Julia without Juno. For example, if I type the following command:

> > A = rand(100,100)

It takes the Juno REPL 5 seconds to render the result.

If I then type this command:

> > A

it takes another 5 seconds for the Juno REPL to render the result.

If I just type a number in the REPL prompt:

> > 3

it displays the result immediately. However, the prompt is frozen for 5 seconds before I can start typing a new command into the prompt.

All of these commands are practically instantaneous in the Julia 1.5.2 REPL (without the Juno IDE).

I’m wondering if all this is normal. I had this problem both in JuliaPro and in Juno installed on top of Atom as described here: [Installation Instructions · Juno Documentation](http://docs.junolab.org/latest/man/installation/)

I searched the internet for a solution, and a suggestion I found was to enable an option called Fallback Renderer. This option appears to be unavailable in the current version of JuliaPro (1.5.2-1).

I’m running this all on Windows 10.