windowManager: Remove timeout on starting X11 services

With Xwayland started on demand, mutter/gnome-shell will spawn Xwayland
and GNOME settings daemon Xsettings.

Currently, gnome-shell uses a timeout of 5 seconds before canceling the
launch and declare failure to start X11 services.

While 5 seconds may seem like a lot of time, when this is executed on a
virtual machine part of a QA tests under load, this causes random
failures.

There is no good value here, we could increase the timeout but it will
always remain racy. Instead, remove the timeout, systemd itself already
has a timeout mechanism (with a much longer wait time).

Thanks to Benjamin Berg <bberg@redhat.com> for finding the root cause
and suggesting the fix.

Part-of: <https://gitlab.gnome.org/GNOME/gnome-shell/-/merge_requests/1888>

diff --git a/js/ui/windowManager.js b/js/ui/windowManager.js
index bacb6dddb5616596bb10facb31ff61ab8dbeed61..d01bac19c7574ed42dd2a61c73f9b6429d2c29ff 100644 (file)
--- a/js/ui/windowManager.js
+++ b/js/ui/windowManager.js
@@ -907,14 +907,7 @@ var WindowManager = class {
         global.display.connect('init-xserver', (display, task) => {
             IBusManager.getIBusManager().restartDaemon(['--xim']);
 
-            /* Timeout waiting for start job completion after 5 seconds */
-            let cancellable = new Gio.Cancellable();
-            GLib.timeout_add_seconds(GLib.PRIORITY_DEFAULT, 5, () => {
-                cancellable.cancel();
-                return GLib.SOURCE_REMOVE;
-            });
-
-            this._startX11Services(task, cancellable);
+            this._startX11Services(task);
 
             return true;
         });
@@ -972,11 +965,11 @@ var WindowManager = class {
         });
     }
 
-    async _startX11Services(task, cancellable) {
+    async _startX11Services(task) {
         let status = true;
         try {
             await Shell.util_start_systemd_unit(
-                'gnome-session-x11-services-ready.target', 'fail', cancellable);
+                'gnome-session-x11-services-ready.target', 'fail', null);
         } catch (e) {
             // Ignore NOT_SUPPORTED error, which indicates we are not systemd
             // managed and gnome-session will have taken care of everything