# How to know what optimization options are been used? How to change it on VS Code? (-o 3)

**URL:** https://discourse.julialang.org/t/how-to-know-what-optimization-options-are-been-used-how-to-change-it-on-vs-code-o-3/18368
**Category:** VS Code
**Created:** [December 6, 2018, 10:44am UTC](https://discourse.julialang.org/t/how-to-know-what-optimization-options-are-been-used-how-to-change-it-on-vs-code-o-3/18368 "2018-12-06T10:44:30Z")
**Posts on this page:** 1
**Page:** 1

<div class="post-metadata">

### Author: ![Juan](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/juan/32/7657_2.png) [@Juan](https://discourse.julialang.org/u/Juan)
#### Post date: [December 6, 2018, 10:44am UTC](https://discourse.julialang.org/t/how-to-know-what-optimization-options-are-been-used-how-to-change-it-on-vs-code-o-3/18368/1 "2018-12-06T10:44:30Z")

</div>

How can I tell VS Code to use Julia with the option “-o 2” or “-o 3”.  
I can’t find the settings.  
How can I know what options are being used from my Julia session?  
What is the suggested option with Julia 1.0?