# How to specify barrier method to use?

**URL:** <https://discourse.julialang.org/t/how-to-specify-barrier-method-to-use/81290>\
**Category:** Optimization (Mathematical)\
**Tags:** jump, optimization\
**Created:** [May 18, 2022, 11:46pm UTC](https://discourse.julialang.org/t/how-to-specify-barrier-method-to-use/81290 "2022-05-18T23:46:11Z")\
**Posts on this page:** 1\
**Showing post:** 6

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**Author:** ![odow](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/odow/32/28685_2.png) [@odow](https://discourse.julialang.org/u/odow)\
**Post date:** [May 21, 2022, 11:55pm UTC](https://discourse.julialang.org/t/how-to-specify-barrier-method-to-use/81290/6 "2022-05-21T23:55:00Z")

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> it was taking about 30 minutes to build the JuMP model  
> the file turned out to be 13.4GB!

Both of those things are very unusual. Do you have a reproducible example?

> I understand that the problem is dense

But ah. This means you have `800_060_001` non-zeros. Just to store that many `Float64` coefficients requires 6 GB of memory. But JuMP assumes problems are sparse, so there will be significant overhead for storing dense problems. In which case, it might not be surprising that it takes that long and consumes so much memory.

Why is your problem dense?

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