# Out of memory error in Juniper.jl

**URL:** <https://discourse.julialang.org/t/out-of-memory-error-in-juniper-jl/91094>\
**Category:** Optimization (Mathematical)\
**Tags:** jump\
**Created:** [December 1, 2022, 1:41pm UTC](https://discourse.julialang.org/t/out-of-memory-error-in-juniper-jl/91094 "2022-12-01T13:41:40Z")\
**Posts on this page:** 1\
**Showing post:** 8

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**Author:** ![this\_josh](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/this_josh/32/42679_2.png) [@this\_josh](https://discourse.julialang.org/u/this_josh)\
**Post date:** [December 2, 2022, 10:19am UTC](https://discourse.julialang.org/t/out-of-memory-error-in-juniper-jl/91094/8 "2022-12-02T10:19:02Z")

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Thanks for your ideas:

1. Previously I was using MostInfeasible, I think this also gave the same error but I’ll try it again.
2. This is currently using MA57 which I don’t think is open-source? MA57 is the fastest out of MA27, MA57, MA87, and MUMPS, when solving this problem as an NLP. It’s possible its suboptimal for solving as a Juniper model.

On the point of MA57, I have set `ma57_automatic_scaling=yes` otherwise when solving with Juniper or as an NLP I get a lot of logs like `Reallocating memory for MA57: lfact (1960656)`. However, I think this could be related to my problems. I have since set it to “no” and branching to :MostInfeasible. I’m just over two hours in and it’s still running, which I believe is longer than it took to get an OOM error before.

So I presume the issue is coming from `MA57`’s automatic rescaling, I’m guessing there’s nothing that can be done about this on the Julia side? As mentioned on a different thread I am using a dated version of `MA57` so perhaps I just need to figure out how to update it.

> [@Incorrect objective type when using MA57 with Ipopt in JuMP](https://discourse.julialang.org/t/incorrect-objective-type-when-using-ma57-with-ipopt-in-jump/90578/8):
>
> I checked what is inside the `coinhsl` archive and it’s an old version of MA57 (`v3.11.0`).

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