[mythtv] Ticket #9223: Sluggish menu when watching a recording

[Mark Kendall]

On 11 February 2011 12:46, John Sturgeon <john.sturgeon at gmail.com> wrote:
> On Feb 10, 2011, at 8:24 PM, MythTV wrote:
>
> #9223: Sluggish menu when watching a recording
> -------------------------------------+--------------------------------
> Reporter:  glemsom@…                |          Owner:  markk
>     Type:  defect                   |         Status:  infoneeded_new
> Priority:  minor                    |      Milestone:  0.24.1
> Component:  MythTV - Video Playback  |        Version:  0.24-fixes
> Severity:  medium                   |     Resolution:
> Keywords:  sluggish menu            |  Ticket locked:  0
> -------------------------------------+--------------------------------
>
> Comment (by markk):
>
> Thanks to John and Brian, I now have a couple of fixes/0.24 binaries that
> display the issue.
>
> Having re-read dgatwood's analysis and comments above, looked at the
> commit that introduced the issue (or moved it from painfully sluggish to
> totally unresponsive a328d996b94f62814cf065e60311d973283ec6c8) and
> considered the Qt version differences, I think the UI thread blocking
> issues are not the issue here.
>
> What is probably relevant is how Qt is handling the event loop internally,
> which I imagine may well be different between cocoa and carbon builds.
> With the cocoa build, the event loop is clearly being processed as
> expected and for carbon - not. Hence no CFRunLoop references as dgatwood
> noted.
>
> So, in the commit I've referenced above, the only piece that would appear
> to change the behaviour of the main event loop is the addition of
> hasPendingEvents() check. The Qt source for QEventDispatcher_mac is chock
> full of #ifdef QT_MAC_USE_COCOA, so trying to unpick the Qt internals
> isn't going to be fruitful.
>
> But by way of a quick and easy test, can someone try removing the
> hasPendingEvents() check in tv_play (there's only one use) and see if that
> helps. It may well simply revert to the previous sluggish behaviour but at
> least that will be progress of sorts.
>
> There is only one instance of hasPendingEvents and that's in
> mythmainwindow.cpp:
> void MythMainWindow::SetDrawEnabled(bool enable)
> {
> [snip]
>         while (QCoreApplication::hasPendingEvents())
>             d->m_setDrawEnabledWait.wait(&d->m_setDrawEnabledLock);
>         return;
>     }
> [snip]
> }
> Did you want me to comment the entire loop?

John

Line 368 of libs/libmythtv/tv_play.cpp (in fixes/0.24 anyway)

regards

Mark