cat /proc/sys/fs/inotify/max_user_watches

It can be raised by adding following line to the /etc/sysctl.conf file:

fs.inotify.max_user_watches = 524288

… and issuing this command to apply the change:

sudo sysctl -p

 

https://blog.jetbrains.com/idea/2010/04/native-file-system-watcher-for-linux/