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Bug 476608

Summary:	Sluggishness reported in gdk_flush
Product:	[Eclipse Project] Platform	Reporter:	Stefan Xenos <sxenos>
Component:	SWT	Assignee:	Platform-SWT-Inbox <platform-swt-inbox>
Status:	CLOSED WORKSFORME	QA Contact:
Severity:	normal
Priority:	P3	CC:	alexandre.koptelov, ericwill
Version:	4.6	Keywords:	triaged
Target Milestone:	---
Hardware:	PC
OS:	Linux
See Also:	https://git.eclipse.org/r/127063 https://git.eclipse.org/c/platform/eclipse.platform.swt.git/commit/?id=aca62e3e174505e5d310af1ac7479886e5882aed
Whiteboard:

Description Stefan Xenos

2015-09-03 16:27:06 EDT

We've received a number of UI freeze reports with gdk_flush on the stack trace. The freezes tend to be on the order of 200-300ms, but since they can happen on every keystroke it impacts the user experience.

The doc on gdk_flush says that the operation is rarely needed by applications:

https://developer.gnome.org/gdk3/stable/gdk3-General.html#gdk-flush

Could someone on the SWT team offer some insight into whether this call is actually necessary and why it might be so slow?


!ENTRY org.eclipse.ui.monitoring 2 0 2015-09-01 12:29:07.385
!MESSAGE UI freeze of 0.26s at 12:29:07.111
!SUBENTRY 1 org.eclipse.ui.monitoring 1 0 2015-09-01 12:29:07.385
!MESSAGE Sample at 12:29:07.245 (+0.134s)
Thread 'main' tid=1 (RUNNABLE)
!STACK 0
java.lang.Exception: Stack Trace
	at org.eclipse.swt.internal.gtk.OS._gdk_flush(Native Method)
	at org.eclipse.swt.internal.gtk.OS.gdk_flush(OS.java:4633)
	at org.eclipse.swt.widgets.Control.update(Control.java:5536)
	at org.eclipse.swt.widgets.Control.update(Control.java:5520)
	at org.eclipse.swt.custom.StyledText.handleKey(StyledText.java:5965)
	at org.eclipse.swt.custom.StyledText.handleKeyDown(StyledText.java:5995)
	at org.eclipse.swt.custom.StyledText$7.handleEvent(StyledText.java:5682)
	at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:84)
	at org.eclipse.swt.widgets.Display.sendEvent(Display.java:4481)
	at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1327)
	at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1351)
	at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1336)
	at org.eclipse.swt.widgets.Widget.sendIMKeyEvent(Widget.java:1413)
	at org.eclipse.swt.widgets.Control.gtk_commit(Control.java:3092)
	at org.eclipse.swt.widgets.Canvas.gtk_commit(Canvas.java:163)
	at org.eclipse.swt.widgets.Widget.windowProc(Widget.java:1946)
	at org.eclipse.swt.widgets.Control.windowProc(Control.java:5590)
	at org.eclipse.swt.widgets.Display.windowProc(Display.java:4717)
	at org.eclipse.swt.internal.gtk.OS._gtk_im_context_filter_keypress(Native Method)
	at org.eclipse.swt.internal.gtk.OS.gtk_im_context_filter_keypress(OS.java:8665)
	at org.eclipse.swt.widgets.Control.filterKey(Control.java:2436)
	at org.eclipse.swt.widgets.Control.gtk_key_press_event(Control.java:3310)
	at org.eclipse.swt.widgets.Composite.gtk_key_press_event(Composite.java:785)
	at org.eclipse.swt.widgets.Widget.windowProc(Widget.java:1965)
	at org.eclipse.swt.widgets.Control.windowProc(Control.java:5590)
	at org.eclipse.swt.widgets.Display.windowProc(Display.java:4717)
	at org.eclipse.swt.internal.gtk.OS._gtk_main_do_event(Native Method)
	at org.eclipse.swt.internal.gtk.OS.gtk_main_do_event(OS.java:9272)
	at org.eclipse.swt.widgets.Display.eventProc(Display.java:1225)
	at org.eclipse.swt.internal.gtk.OS._g_main_context_iteration(Native Method)
	at org.eclipse.swt.internal.gtk.OS.g_main_context_iteration(OS.java:2422)
	at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3428)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine$4.run(PartRenderingEngine.java:1127)
	at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:336)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.run(PartRenderingEngine.java:1018)
	at org.eclipse.e4.ui.internal.workbench.E4Workbench.createAndRunUI(E4Workbench.java:156)
	at org.eclipse.ui.internal.Workbench$5.run(Workbench.java:654)
	at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:336)
	at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:598)
	at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:150)
	at org.eclipse.ui.internal.ide.application.IDEApplication.start(IDEApplication.java:139)
	at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:196)
	at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:134)
	at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:104)
	at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:380)
	at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:235)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:483)
	at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:669)
	at org.eclipse.equinox.launcher.Main.basicRun(Main.java:608)
	at org.eclipse.equinox.launcher.Main.run(Main.java:1515)
	at org.eclipse.equinox.launcher.Main.main(Main.java:1488)

Comment 1 Alexander Kurtakov

2015-09-04 09:55:44 EDT

TBH I always wondered why all the flushing but never investigated it. Help is more than welcome.

Comment 2 Alexander Kurtakov

2016-04-15 13:11:12 EDT

Stefan, do you still get such reports? I would say let's remove gdk_flush for Oxygen M1 where it looks useless so we have more time to revert if/where needed.

Comment 3 Alexander Koptelov

2016-06-20 07:50:02 EDT

(In reply to Alexander Kurtakov from comment #2)
> Stefan, do you still get such reports? I would say let's remove gdk_flush
> for Oxygen M1 where it looks useless so we have more time to revert if/where
> needed.

Hi Alexander!

We also get the report like that from our Eclipse-based application. It would be very nice to get rid of them. Please ping me if any additional info is needed.

Comment 4 Stefan Xenos

2016-06-20 10:35:11 EDT

> Stefan, do you still get such reports?

Yes, I still get these reports. We enable the freeze reporting tool for most Eclipse users within Google.

Unfortunately, we currently only report this sort of data when the user indicates they had a problem... and since these reports are infrequent, it's hard to know for certain that a freeze of this form is fixed.

However, with that qualification, I will happily pass along any further reports I get on this topic.

Comment 5 Eclipse Genie

2018-08-04 13:11:08 EDT

New Gerrit change created: https://git.eclipse.org/r/127063

Comment 6 Eclipse Genie

2018-08-04 15:17:28 EDT

Gerrit change https://git.eclipse.org/r/127063 was merged to [master].
Commit: http://git.eclipse.org/c/platform/eclipse.platform.swt.git/commit/?id=aca62e3e174505e5d310af1ac7479886e5882aed

Comment 7 Eric Williams

2018-12-14 13:37:33 EST

gdk_flush() is gone in GTK4, not sure if it makes much sense to remove it in SWT-GTK3.

Comment 8 Eric Williams

2019-02-20 14:06:25 EST

(In reply to Eric Williams from comment #7)
> gdk_flush() is gone in GTK4, not sure if it makes much sense to remove it in
> SWT-GTK3.

Aaaaand we've removed it from the GTK3 side of things too. Closing this ticket now.