# Error in memory emphasis command

**URL:** <https://discuss.ampl.com/t/error-in-memory-emphasis-command/2189>\
**Category:** Support\
**Created:** [August 13, 2025, 2:58am UTC](https://discuss.ampl.com/t/error-in-memory-emphasis-command/2189 "2025-08-13T02:58:13Z")\
**Posts on this page:** 2\
**Page:** 1

<div class="post-metadata">

**Author:** ![qiaolunzhang](https://avatars.discourse-cdn.com/v4/letter/q/898d66/32.png) [@qiaolunzhang](https://discuss.ampl.com/u/qiaolunzhang)\
**Post date:** [August 13, 2025, 2:58am UTC](https://discuss.ampl.com/t/error-in-memory-emphasis-command/2189/1 "2025-08-13T02:58:13Z")

</div>

I have the following settings for a run file:

`option cplex_options 'memoryemphasis=1 mipgap=1e-9 threads=8 timelimit=18000';`

It works in old version of ampl, but now it shows the following error:

CPLEX 22.1.1: Unknown option or invalid key “memoryemphasis”

How can I set the memoryemphasis in the new version of ampl for reducing memory consumption?

Thank you!

---

<div class="post-metadata">

**Author:** ![marcos](https://sea1.discourse-cdn.com/flex019/user_avatar/discuss.ampl.com/marcos/32/154_2.png) [@marcos](https://discuss.ampl.com/u/marcos)\
**Post date:** [August 20, 2025, 4:49pm UTC](https://discuss.ampl.com/t/error-in-memory-emphasis-command/2189/2 "2025-08-20T16:49:11Z")

</div>

Hi @qiaolunzhang ,

Thanks for your message! We have heavily changed (and enhanced) our Cplex driver, but that option was missing.

Could you try reinstalling the new version of Cplex and trying again your options? You can load them directly with:

```auto
ampl.solve(solver="cplex", cplex_options="memoryemphasis=1 mipgap=1e-9 threads=8 timelimit=18000")

```

Now Cplex supports all the extended set of modeling features from MP, maybe it could be helpful to you in the future:

> **[Modeling guide for MP-based AMPL solvers — AMPL MP Documentation](https://mp.ampl.com/model-guide.html)**