[Bug 58658] New: IK Multimedia Amplitube 5: GUI rendering periodically hangs.

[WineHQ Bugzilla]

http://bugs.winehq.org/show_bug.cgi?id=58658

Bug ID: 58658
           Summary: IK Multimedia Amplitube 5: GUI rendering periodically
                    hangs.
           Product: Wine
           Version: 10.14
          Hardware: x86-64
                OS: Linux
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: -unknown
          Assignee: [e-mail]
          Reporter: [e-mail]
      Distribution: ---

Created attachment 79236
  --> http://bugs.winehq.org/attachment.cgi?id=79236
Diagram showing GUI drawing lag spike behavior in Amplitube 5

Amplitube 5 (a guitar and bass amp/effect sim program) has a problem via WINE
where rendering of the GUI periodically hangs. Here are some things that might
help:

- These lag spikes DON'T occur in the original version on Windows.
- These spikes seem to ONLY affect the drawing of the GUI. (Audio processing is
unaffected, and mouse clicks are still registered even when the rendering is
hitching.)
- The lag spikes are extremely predictable (dare I say metronomic). From what I
can tell they happen almost once per second, every second. They also seem to
last about half a second, every time. (I've attached a silly diagram to show
how it feels like the spikes are happening.)
- I use this program very regularly, and I have noticed that this bug has been
around for a while, across a few versions of WINE. I can't say whether or not
it is a regression from older versions of WINE as a lot of things have changed
on my system, but I'm sure that it isn't new to 10.14.
- This may be an interesting, unrelated coincidence... But the default
metronome setting in Amplitube happens to be 120bpm (2hz), and the timing of
the GUI lag spikes is so regular and predictable that if you turn the metronome
on and hit play, you will find that they line up exactly with the timing of the
beats/clicks. (Where you can count 1,2,3,4 and visually see the program's GUI
draw, lag, draw, lag...) When I first noticed this I changed the internal bpm
setting to a different value, thinking that it might be connected, but that did
not seem to change the frequency of the lag spikes (they continued happening at
~1 spike per second).
- I have tested this on a standard WINEPREFIX containing only IK Multimedia
application installs. But I have also tested this using DXVK library overrides.
I know that bug reports here are for vanilla WINE installs only, but I just
want to mention that this behavior seems to be consistent whether in both
contexts.
- I should also mention that I don't see any output in the terminal when these
spikes are happening. To the untrained eye, there's nothing that I can see that
is hinting at what might be causing the visual hitching.

Aside from these annoying GUI drawing hitches, Amplitube 5 works very nicely in
WINE, so I'm hoping that we can figure something out. :)

If there is anything else I can share with the team to help diagnose and debug
this problem I'd be happy to help!

[Bug 58658] IK Multimedia Amplitube 5: GUI rendering periodically hangs.

[WineHQ Bugzilla]

http://bugs.winehq.org/show_bug.cgi?id=58658

Emmet O'Neill  changed:

What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |[e-mail]

--- Comment #1 from Emmet O'Neill  ---
Created attachment 79247
  --> http://bugs.winehq.org/attachment.cgi?id=79247
laptop log (+d3d,+timestamp,+fps)

Here's a log that I took on my low-powered laptop using
`WINEDEBUG=+d3d,+timestamp,+fps`. The application runs pretty poorly in general
on this laptop and the hitching seems to be worse, so it's difficult to tell
how consistent the hitch timing is. (NOTE: This laptop is also running an older
version of WINE, 8.19, and the hitching seems to be similar.)

This is my first time trying to seriously debug a WINE issue, so please let me
know if there is anything else I should try, other WINEDEBUG settings I should
use, etc. :)

[Bug 58658] IK Multimedia Amplitube 5: GUI rendering periodically hangs.

[WineHQ Bugzilla]

http://bugs.winehq.org/show_bug.cgi?id=58658

--- Comment #2 from Emmet O'Neill  ---
I forgot to mention the context of the "laptop log" attachment.

While taking this log, I simply opened Amplitube, turned on the metronome
click, and then hit the "play" button to start the playback timer. (This is a
decent way to visualize the hitching without too many other things going on, i
think.) I let the program run like this for a few seconds before hitting the
close button, saying "No" on the save prompt dialog, and ending the process.