[10] Review request for 8176844: Menus not always selected properly with GTK 3

[Philip Race]

AWT used to have really bad at X11 remote display and
it was looked at a few times and I think it was improved
noticeably when we could get rid of  "round trip" requests.
I think Jim had a hand in some of that work.

So I am sure a round trip - or similar - is bad for performance.

If you want to measure the effect of such change, remote display to
your desktop from a machine in a geographically distant site.

It is the latency that kills performance, not the bandwidth.

-phil.

On 4/4/17, 3:43 PM, David Hill wrote:
> On 4/4/17, 1:27 PM, Semyon Sadetsky wrote:
>> Hello Kevin & David,
>>
>> Please review the fix for jfx9:
>>
>> bug: https://bugs.openjdk.java.net/browse/JDK-8176844
>>
>> webrev: http://cr.openjdk.java.net/~ssadetsky/8176844/
>>
>> --Semyon
>>
>
> Semyon,
>
> I have been sitting here for a while thinking about adding
> gdk_display_sync(gdk_display_get_default());
>
> I can see why this might address many issues, as it flushes the 
> pipeline and waits for the X11 server to catch up. That is balanced 
> out by a historical distrust of using XSync in any situation where the 
> consequences.
>
> Part of me thinks it is minimal overhead though, the other part does 
> not like stalling the asynchronous X11 design.
>
> The other part of me would like to use this only for the window events 
> that need it, instead of all of them.
>
> and I found this in hte GTK docs:
> gdk_events_pending ()
> Waits for a GraphicsExpose or NoExpose event from the X server. This 
> is used in the GtkText and GtkCList widgets in GTK+ to make sure any 
> GraphicsExpose events are handled before the widget is scrolled.
>
> so perhaps this should be used in some cases (like setVisible).
>
> sigh.
>
> Will try to make up my mind tomorrow.
>
> Dave.
>