Apparently CrashPlan eats inotify watchers

As a brief follow-up to my last post, I had a problem trying to remote into my newly installed Ubuntu box today.  As I mentioned in that post, I'm using xRDP for my remote GUI access and I'm tunneling it over SSH.  When I connected to xRDP, I logged in and was greeted by the Ubuntu lock screen for my running session.  So I entered my password, hit "enter", and waited.  And waited.  And waited some more.  My session just never unlocked.

OK, so apparently xRPD is freaking out.  I already have a an SSH session open, so I'll just restart the service and maybe that will clear up the problem.  So I ran service xrdp restart and it told me:

Failed to add /run/systemd/ask-password to directory watch: No space left on device

That didn't seem right.  I had plenty of disk space and plenty of RAM - what could possibly be out of space?  So naturally I asked the internet, which led me to this Stack Exchange post.  Turns out that CrashPlan has a habit of eating up inotify watchers, which is what I was actually out of.  Stopping the CrashPlan service fixed the problem.  Fortunately, I don't need CrashPlan anymore, so that shouldn't be a problem again.