Configuring Linux for Many Watch Folders

To run many (>100) push Watch Folders on Linux computers, adjust three system settings and then reload the sysctl.conf file to activate them.

Increase the maximum number of watches allowed by the system.
Retrieve the current value by running the following command:
```
$ cat /proc/sys/fs/inotify/max_user_watches
8192
```
To permanently increase the number of available watches (to a value that is greater than the number of files to watch, such as 524288), add the configuration to /etc/sysctl.conf:
```
$ sudo echo "fs.inotify.max_user_watches=524288" >> /etc/sysctl.conf
```
Increase the maximum number of inotify instances, which correspond to the number of allowed Watch Services instances.
Retrieve the current value by running the following command:
```
$ cat /proc/sys/fs/inotify/max_user_instances
128
```
On many systems, the default value is 128, meaning only 128 watches can be created. To permanently increase the number available (to a value that is greater than the number of desired Watch Folder instances, such as 1024), add the configuration to /etc/sysctl.conf:
```
$ sudo echo "fs.inotify.max_user_instances=1024" >> /etc/sysctl.conf
```
Increase the open file limit.
Retrieve the current value by running the following command:
```
$ cat /proc/sys/fs/file-max
794120
```
To permanently increase the open file limit (to a value that is greater than the number of desired watches, such as 2097152), add the configuration to /etc/sysctl.conf:
```
$ sudo echo "fs.file-max=2097152" >> /etc/sysctl.conf
```
Reload systemd settings to activate the new settings.
To reload systemd settings, either reboot the machine or run the following command:
```
$ sudo sysctl -p /etc/sysctl.conf
```