PyCharm & Linux FS Notifier

Native file system watcher for Linux

If you’re an IntelliJ user working under Linux you’ve probably seen that boring “Synchronizing files…” spinning icon in a left corner of a status bar. It is there because for an intelligent IDE it is a must to be in the know about any external changes in files it working with – e.g. changes made by VCS, or build tools, or code generators etc. On Windows and Mac OS X native file system watchers used to facilitate this task but on Linux the only option was to recursively scan directory tree. Now you’re welcome to give a try to native file system watcher for Linux.
File system watcher requires inotify(7) facility. It is in mainstream kernel for more than two years (since 2.6.13, and in glibc since 2.4) so chances are your distribution don’t missing it. The sign of inotify availability in a system is a presence of /proc/sys/fs/inotify/ directory.
Download and setup
File system watcher is a single binary executable (fsnotifier) and can be downloaded directly from our Git repository. It should be named ‘fsnotifier’, placed into bin/ directory of your IDE and granted execution rights. Inotify requires a “watch handle” to be set for each directory it monitors. Unfortunately, the default limit of watch handles may not be enough for reasonably sized projects (e.g. IntelliJ IDEA sources contain 30000+ directories). The current limit can be verified by executing:

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

64-bit systems
If your system is strictly 64-bit (i.e. doesn’t contains 32-bit runtime libraries in /lib32 directory) you should download 64-bit version here. Rename downloaded file to “fsnotifier”, rest of setup is same.