
##  OS file watch limit reached
When running `yarn run dev` (or `npm run dev`), you may encounter the following error.
```sh
{
    "title": "OS file watch limit reached error"
}
---
$ yarn run dev
...
Caused by: - OS file watch limit reached
```
```adcard
```
### Cause
This error occurs when the Linux kernel's <mark>inotify</mark> file watch limit is exceeded.

Development servers like Next.js, Vite, and Webpack simultaneously watch a large number of files in your project to detect changes and perform <mark>Hot Reload</mark>.  
If the default value of `fs.inotify.max_user_watches` is too low, the number of files to watch exceeds the limit and the error occurs.
```sh
{
    "title": "Check current inotify watch limit"
}
---
$ cat /proc/sys/fs/inotify/max_user_watches
8192
```
### Solution
You can resolve this by increasing the `fs.inotify.max_user_watches` value using `sysctl`.

First, apply it immediately to the current session.
```sh
{
    "title": "Apply immediately (current session)"
}
---
$ sudo sysctl fs.inotify.max_user_watches=524288
$ sudo sysctl -p
```
Add a permanent setting to `/etc/sysctl.conf` to persist the change across reboots.
```sh
{
    "title": "Persist across reboots"
}
---
$ echo fs.inotify.max_user_watches=524288 | sudo tee -a /etc/sysctl.conf
$ sudo sysctl -p
```


How to fix the 'OS file watch limit reached' error when running yarn dev by increasing the Linux inotify file watch limit

Fixing OS File Watch Limit Reached Error

OS file watch limit reached

Cause

Solution