lsyncdの制限
Be aware that the kernel limits the number of watches. You can see the limit in /proc/sys/fs/inotify/max_user_watches which is usually set to 8192. This means lsyncd cannot watch more than 8192 directories unless you change the kernel setting. Lsyncd itself has no limits.
なんだって。
なのでsysctl.confに
fs.inotify.max_user_watches = 65536
を書いて
sudo sysctl -p