> For the complete documentation index, see [llms.txt](https://old.docs.volmit.com/iris/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://old.docs.volmit.com/iris/pregeneration.md).

# Pregeneration

Pregenerating your world will enhance performance by a lot. If all the blocks are already placed, your server can handle much more traffic, than when they have to be generated live.

{% hint style="warning" %}
Thinking about other plugins to pregenerate? Stop. They are not [compatible](/iris/plugin/compatibility.md).
{% endhint %}

**Create a world** without any players on it (see [Getting Started](/iris/getting-started.md#introduction) for how you do that)

**Pick a size**

{% hint style="info" %}
For selecting the right size, we recommend a number between 2.5k and 12.5k. 2.5k is more than enough for 10 players per day, and 12.5k is more than enough for over a hundred players per day.

This is the value you will use as `<radius>` in the next step.

**Notes:**&#x20;

* Higher sizes cause increasingly longer generation times.
* Be prepared to **wait hours up to days** for your generation to be finished.
* The time depends on the size of the pregen and the hardware of the server.
* You can always expand an existing generation -> **start small**.
  {% endhint %}

**Pick a center**

* Generally you don't need to specify a center
* if you want to set the center at your location, use `center=self`
* if you want to set the center by a coordinate, use `center=0,0`&#x20;

**Run the pregen**:

* If you are in the world: `/iris pregen start <radius>`
* If you are in the server: `/iris pregen start <radius> world=<worldName>`
* If you are in the console: `iris pregen start <radius> world=<worldName>`

{% hint style="info" %}
The `<worldName>` is the name of the world.

The `<radius>` to select is based on preference and use-case.

Entering a radius of 1000 gives you a 2000 by 2000 world, which means you can travel 1000 blocks in any direction from the center of the world (0, 0). Here is a diagram:
{% endhint %}

![/iris pregen 1000](https://3612174173-files.gitbook.io/~/files/v0/b/gitbook-legacy-files/o/assets%2F-LH1Gn8DuUpLfebICk_2%2F-MgCRziDvhYIc3l2faHV%2F-MgCSFhmB7Nuu0DkBEaH%2Fimage.png?alt=media\&token=3a7259ce-a6d1-4da5-bfa4-9236a0e331d9)

### Restarts

If you need to restart your server during a pregeneration, it is safe to do so at any time. You can ignore any errors about threads not shutting down.

**After starting your server again, resume the pregen with the same command you entered before. Iris will skip any chunks that were already generated.**

{% hint style="danger" %}
Removing Iris after pregenerating can cause numerous issues. See the [FAQ entry](/iris/plugin/faq.md#uninstalling-iris) about this.
{% endhint %}