When your application is ready to get deployed, here are some tips to improve your WebSocket server.
### Open Connection Limit
On Unix systems, every user that connects to your WebSocket server is represented as a file somewhere on the system.
As a security measurement of every Unix based OS, the number of "file descriptors" an application may have open at a time is limited - most of the time to a default value of 1024 - which would result in a maximum number of 1024 concurrent users on your WebSocket server.
In addition to the OS restrictions, this package makes use of an event loop called "stream_select", which has a hard limit of 1024.
#### Increasing the maximum number of file descriptors
The operating system limit of open "file descriptors" can be increased using the `ulimit` command. The `-n` option modifies the number of open file descriptors.
```bash
ulimit -n 10000
```
The `ulimit` command only **temporarily** increases the maximum number of open file descriptors. To permanently modify this value, you can edit it in your operating system `limits.conf` file.
You are best to do so by creating a file in the `limits.d` directory. This will work for both Red Hat & Ubuntu derivatives.
```bash
$ cat /etc/security/limits.d/laravel-echo.conf
laravel-echo soft nofile 10000
```
The above example assumes you will run your echo server as the `laravel-echo` user, you are free to change that to your liking.
#### Changing the event loop
To make use of a different event loop, that does not have a hard limit of 1024 concurrent connections, you can either install the `ev` or `event` PECL extension using:
```bash
sudo pecl install ev
# or
sudo pecl install event
```
#### Deploying on Laravel Forge
If your are using [Laravel Forge](https://forge.laravel.com/) for the deployment [this article by Alex Bouma](https://alex.bouma.dev/installing-laravel-websockets-on-forge) might help you out.
## Keeping the socket server running with supervisord
The `websockets:serve` daemon needs to always be running in order to accept connections. This is a prime use case for `supervisor`, a task runner on Linux.
First, make sure `supervisor` is installed.
```bash
# On Debian / Ubuntu
apt install supervisor
# On Red Hat / CentOS
yum install supervisor
systemctl enable supervisord
```
Once installed, add a new process that `supervisor` needs to keep running. You place your configurations in the `/etc/supervisor/conf.d` (Debian/Ubuntu) or `/etc/supervisord.d` (Red Hat/CentOS) directory.
Within that directory, create a new file called `websockets.conf`.
Once created, instruct `supervisor` to reload its configuration files (without impacting the already running `supervisor` jobs).
```bash
supervisorctl update
supervisorctl start websockets
```
Your echo server should now be running (you can verify this with `supervisorctl status`). If it were to crash, `supervisor` will automatically restart it.
Please note that, by default, just like file descriptiors, `supervisor` will force a maximum number of open files onto all the processes that it manages. This is configured by the `minfds` parameter in `supervisord.conf`.
If you want to increase the maximum number of open files, you may do so in `/etc/supervisor/supervisord.conf` (Debian/Ubuntu) or `/etc/supervisord.conf` (Red Hat/CentOS):
After changing this setting, you'll need to restart the supervisor process (which in turn will restart all your processes that it manages).
## Debugging supervisor
If you run into issues with Supervisor, like not supporting a lot of connections, consider checking the [Ratched docs on deploying with Supervisor](http://socketo.me/docs/deploy#supervisor).
