Clementine's monitoring of music library results in all kinds of crashes when too many file handles are open

[Ken]

For the past few days, I've been getting a lot of errors from clementine. Some errors are this:

    pa_threaded_mainloop_new() failed
    LibraryBackend: unable to open database file Unable to fetch row

Sometimes, it's a gstreamer error:

    GStreamer-CRITICAL **: gstsystemclock: write control failed in wakeup_async: 24:Too many open files

Both of those show up in GUI dialog boxes. Outputted to the console, I see errors like this, repeated for dozens of directories in my Music collection:

    2:05:53.962 WARN unknown QFileSystemWatcher: failed to add paths: /home/(redacted)/Music/Nastasia, Nina & White, Jim

Then when you try to play music, either the database error from above shows, the gstreamer error is shown in a dialog box, or the app just exits.

There are two things I find resolve the problem.

1. Splitting my music collection in half and putting half in one directory and half in another, then only using one directory at once. Because this solves the problem, I know that no particular file is tripping up clementine.

2. Disable the "Preferences -> Monitor the library for changes" resolves the problem entirely, regardless of the size of my music collection.

I believe that Clementine is using QFileWatcher to watch changes to my music collection, and now my music collection is large enough that this behavior causes Clementine to run out of file handles.

ProblemType: Bug
DistroRelease: Ubuntu 12.10
Package: clementine 1.0.1+dfsg-2ubuntu3
ProcVersionSignature: Ubuntu 3.5.0-22.34-generic 3.5.7.2
Uname: Linux 3.5.0-22-generic x86_64
ApportVersion: 2.6.1-0ubuntu10
Architecture: amd64
Date: Wed Jan 30 11:59:55 2013
EcryptfsInUse: Yes
MarkForUpload: True
ProcEnviron:
 LANGUAGE=
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=en_US.UTF-8
 SHELL=/usr/bin/fish
SourcePackage: clementine
UpgradeStatus: No upgrade log present (probably fresh install)

[Frank Lister (flister98)]

To be considered complete, a bug report should normally contain:

What version of Ubuntu are you running?
What version of the package are you using?
The actions taken to produce the problem?
Whether or not it is possible for the reporter to reproduce the bug?
The expected result of these actions?
The actual result of these actions?

[Ken (kkinder)]

Somehow I thought ubuntu-bug would have reported all that metadata.

Kubuntu 12.10, Clementine 1.0.1+dfsg-2ubuntu3.

The actions and reproduction steps are thoroughly documented in my original report. In fact, I think I pretty well explained what the actual crash is -- all that needs to happen is (1) increase the file limit for Clementine or (2) have Clementine realize that it's going to exceed the file limit and not watch the entire music folder. Tell the user about that, of course.

[Ken (kkinder)]

Also, it isn't related to Clementine because Clementine is not a KDE app, but I am using the kubuntu-ppa-beta-quantal ppa (http://ppa.launchpad.net/kubuntu-ppa/beta/ubuntu).