Nixpkgs: Nixos 15.09 regression - Mousepad exponential stdout as function of instance count

[jraygauthier]

Issue description

Starting with _nixos 15.09_, when executing mousepad from the terminal I
noticed that I was getting the following output (5 lines of output):

$ mousepad 

(mousepad:2633): GtkSourceView-CRITICAL **: gtk_source_style_scheme_get_id: assertion 'GTK_IS_SOURCE_STYLE_SCHEME (scheme)' failed

(mousepad:2633): GLib-CRITICAL **: g_variant_new_string: assertion 'string != NULL' failed

(mousepad:2633): GtkSourceView-CRITICAL **: gtk_source_style_scheme_get_id: assertion 'GTK_IS_SOURCE_STYLE_SCHEME (scheme)' failed

(mousepad:2633): GLib-CRITICAL **: g_variant_new_string: assertion 'string != NULL' failed

(mousepad:2633): GtkSourceView-CRITICAL **: gtk_source_style_scheme_get_id: assertion 'GTK_IS_SOURCE_STYLE_SCHEME (scheme)' failed

When I launch another instance from another terminal, I now have the following
output in the first terminal (25 lines of output):

$ mousepad 

(mousepad:2633): GtkSourceView-CRITICAL **: gtk_source_style_scheme_get_id: assertion 'GTK_IS_SOURCE_STYLE_SCHEME (scheme)' failed

(mousepad:2633): GLib-CRITICAL **: g_variant_new_string: assertion 'string != NULL' failed

(mousepad:2633): GtkSourceView-CRITICAL **: gtk_source_style_scheme_get_id: assertion 'GTK_IS_SOURCE_STYLE_SCHEME (scheme)' failed

(mousepad:2633): GLib-CRITICAL **: g_variant_new_string: assertion 'string != NULL' failed

(mousepad:2633): GtkSourceView-CRITICAL **: gtk_source_style_scheme_get_id: assertion 'GTK_IS_SOURCE_STYLE_SCHEME (scheme)' failed

(mousepad:2633): GtkSourceView-CRITICAL **: gtk_source_style_scheme_get_id: assertion 'GTK_IS_SOURCE_STYLE_SCHEME (scheme)' failed

(mousepad:2633): GLib-CRITICAL **: g_variant_new_string: assertion 'string != NULL' failed

(mousepad:2633): GtkSourceView-CRITICAL **: gtk_source_style_scheme_get_id: assertion 'GTK_IS_SOURCE_STYLE_SCHEME (scheme)' failed

(mousepad:2633): GLib-CRITICAL **: g_variant_new_string: assertion 'string != NULL' failed

(mousepad:2633): GtkSourceView-CRITICAL **: gtk_source_style_scheme_get_id: assertion 'GTK_IS_SOURCE_STYLE_SCHEME (scheme)' failed

(mousepad:2633): GtkSourceView-CRITICAL **: gtk_source_style_scheme_manager_get_scheme: assertion 'scheme_id != NULL' failed

(mousepad:2633): GtkSourceView-CRITICAL **: gtk_source_style_scheme_get_id: assertion 'GTK_IS_SOURCE_STYLE_SCHEME (scheme)' failed

(mousepad:2633): GLib-CRITICAL **: g_variant_new_string: assertion 'string != NULL' failed

(mousepad:2633): GtkSourceView-CRITICAL **: gtk_source_style_scheme_get_id: assertion 'GTK_IS_SOURCE_STYLE_SCHEME (scheme)' failed

(mousepad:2633): GLib-CRITICAL **: g_variant_new_string: assertion 'string != NULL' failed

(mousepad:2633): GtkSourceView-CRITICAL **: gtk_source_style_scheme_get_id: assertion 'GTK_IS_SOURCE_STYLE_SCHEME (scheme)' failed

(mousepad:2633): GtkSourceView-CRITICAL **: gtk_source_style_scheme_get_id: assertion 'GTK_IS_SOURCE_STYLE_SCHEME (scheme)' failed

(mousepad:2633): GtkSourceView-CRITICAL **: gtk_source_style_scheme_manager_get_scheme: assertion 'scheme_id != NULL' failed

(mousepad:2633): GtkSourceView-CRITICAL **: gtk_source_style_scheme_get_id: assertion 'GTK_IS_SOURCE_STYLE_SCHEME (scheme)' failed

(mousepad:2633): GLib-CRITICAL **: g_variant_new_string: assertion 'string != NULL' failed

(mousepad:2633): GtkSourceView-CRITICAL **: gtk_source_style_scheme_get_id: assertion 'GTK_IS_SOURCE_STYLE_SCHEME (scheme)' failed

(mousepad:2633): GLib-CRITICAL **: g_variant_new_string: assertion 'string != NULL' failed

(mousepad:2633): GtkSourceView-CRITICAL **: gtk_source_style_scheme_get_id: assertion 'GTK_IS_SOURCE_STYLE_SCHEME (scheme)' failed

(mousepad:2633): GtkSourceView-CRITICAL **: gtk_source_style_scheme_manager_get_scheme: assertion 'scheme_id != NULL' failed

(mousepad:2633): GtkSourceView-CRITICAL **: gtk_source_style_scheme_get_id: assertion 'GTK_IS_SOURCE_STYLE_SCHEME (scheme)' failed

At about 5 instances, it begins to take a noticeable amount of time before
your new instance appear.

At about 7-8 instances, its coffee time.

Was working well on _nixos 14.12_.

I got the same problem using _nixos 16.03_.

Steps to reproduce

• Open a terminal
• $ mousepad.
• Open another terminal

• $ mousepad until the instance no longer appear immediatly as it is busy printing
  its output.

  Technical details

• System: nixos 16.03

• Nix version: irrelevant
• Nixpkgs version: latest of the nixos 16.03 branch

[vcunat]

Interesting. When I select a color scheme (the default is _none_), the error messages stop appearing completely, but the startup time blowup remains.

[volth]

'none' was removed from GtkSourceView. https://bugzilla.xfce.org/show_bug.cgi?id=11663

[jraygauthier]

Reading 12134 – Running multiple mousepad instances shows a huge dbus trafic with dconf-related stuff, the issue should have been fixed upstream.

[vcunat]

Nixpkgs is probably still affected, as we're at the freshest mousepad release, from February 2015.

[yegortimoshenko]

Here is the patch: https://github.com/xfce-mirror/mousepad/commit/309f6177d2c47070676d6c733e29952c63c110ba.patch

I'll backport it.