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IDProjectCategoryView StatusLast Update
0006707ardourbugspublic2016-01-22 22:37
Reporterdon3 Assigned To 
PrioritynormalSeveritymajorReproducibilityrandom
Status newResolutionopen 
PlatformLinuxOSFedoraOS Version21
Product Version4.4 
Summary0006707: Random JACK "zombified" error when scrolling/zooming breaks session
DescriptionMost recently seen on Ardour nightly 4.4.463.
Fedora 21 with CCRMA extensions
kernel: 4.0.5-200.rt4.3.fc21.ccrma.x86_64+rt
XFCE in TigerVNC session

Sometimes when adding fader automation to a track in a recorded session, I'll zoom out from where I've just created a first automation point (in Draw mode) and scroll back so I can see the start and verify that the point Ardour creates at time=0 is in the intended place. Occasionally when I do that scrolling-back operation, I get an pop-up with a JACK "zombified" error, and (IIRC) I can't save the session after that, so any work I've done since the last Save is toast. This the "random" part of the bug report. Not 100% sure, but I think it tends to happen more when I scroll rather quickly (using shift-scrollwheel).

Furthermore, once that has happened, restarting Ardour on the same session produces the zombified error immediately after it's loaded. I'm thinking (but don't remember for sure) that in the past, I was able to restart Ardour several times, and possibly restart JACK (using qjackctl), and eventually get a successful load. However, when this has happened more recently, restarting has never worked. (Not in the several tries I have the patience for, anyway.) Then I discovered that if I remove instant.xml, the session loads without complaint, and all is well after manually restoring a number of preferences/settings (eg, I have to re-open the mixer window, resize things, etc).

This happened on a session just yesterday. I saved the failing instant.xml, and the one that was eventually rebuilt as I continued to work on the session after that. I can attach both, but for now I'll upload just a diff, since there are only a few differing lines. Note: Some of the differences reflect settings that I changed between the two - mixer strip widths, for example. I didn't attempt to set window geometries back the exact original values. I can try harder if that would help.
Steps To ReproduceRoughly:
 1: Create a session with multiple tracks. (Not sure the number of tracks is important. My most recent one has 16 tracks and 4 buses (in addition to Master) but I've seen this with a lot fewer of both. In my case I recorded ~1 hour of audio, but that may not be needed.)
 2: Enable fader automation on some number of tracks, switch to Draw mode, move to some time > 0 (let's say 0000010:0000040 minutes in), zoom in several steps (for me the editor spans maybe 1 second to a few minutes of time), create a point in 1 or more tracks.
 3: Zoom back out (ctrl-scrollwheel) so that maybe 10 minutes of the timeline is visible, scroll (shift-scrollwheel, quickly?) back so that time=0 is visible on the left.
 4: Observe random "zombified" error pop-up while scrolling, or just after. (For me, maybe 2-5% of the time.)
 5: Optionally utter expletives; exit session.
 6: Restart Ardour on the session. Session windows (Editor and Mixer in my case) open, but "zombified" pop-up appears immediately after that.
 7: Move/Rename instant.xml
 8: Restart Ardour on the session again. No "zombified" error.
TagsNo tags attached.

Activities

don3

2015-12-16 01:34

reporter  

instant.zombie-working.xml.diff (2,337 bytes)   
----------------------------------------------------------------4,5c4,5
<   <Editor id="18" mixer-width="Wide" zoom-focus="ZoomFocusPlayhead" zoom="2097152" snap-to="SnapToMark" snap-mode="SnapMagnetic" internal-snap-to="SnapToMark" internal-snap-mode="SnapMagnetic" pre-internal-snap-to="SnapToMinutes" pre-internal-snap-mode="SnapMagnetic" edit-point="EditAtMouse" visible-track-count="-1" playhead="307369984" left-frame="0" y-origin="476.000000" show-measures="no" maximised="no" follow-playhead="no" stationary-playhead="no" region-list-sort-type="ByEndInFile" mouse-mode="MouseContent" join-object-range="yes" show-editor-mixer="no" show-editor-list="yes" editor-list-page="1" show-marker-lines="yes" nudge-clock-value="1824">
<     <geometry x-size="1385" y-size="845" x-pos="338" y-pos="22" edit-horizontal-pane-pos="1254" notebook-shrunk="0" edit-vertical-pane-pos="644"/>
---
>   <Editor id="18" zoom-focus="ZoomFocusPlayhead" zoom="146919" snap-to="SnapToMark" snap-mode="SnapMagnetic" internal-snap-to="SnapToBeat" internal-snap-mode="SnapOff" pre-internal-snap-to="SnapToMark" pre-internal-snap-mode="SnapMagnetic" edit-point="EditAtMouse" visible-track-count="-1" playhead="282140768" left-frame="267245661" y-origin="816.000000" show-measures="no" maximised="no" follow-playhead="no" stationary-playhead="no" region-list-sort-type="ByEndInFile" mouse-mode="MouseObject" join-object-range="no" show-editor-mixer="no" show-editor-list="yes" editor-list-page="0" show-marker-lines="yes" nudge-clock-value="240000">
>     <geometry x-size="1579" y-size="845" x-pos="200" y-pos="21" edit-horizontal-pane-pos="1470" notebook-shrunk="0" edit-vertical-pane-pos="645"/>
----------------------------------------------------------------10,12c10
<     <Selection>
<       <Marker id="6822" start="yes"/>
<     </Selection>
---
>     <Selection/>
----------------------------------------------------------------15,16c13,14
<   <Mixer narrow-strips="no" show-mixer="yes" maximised="no">
<     <geometry x-size="1731" y-size="761" x-pos="12" y-pos="202" x-off="0" y-off="0" mixer-rhs-pane1-pos="255" mixer-list-hpane-pos="120"/>
---
>   <Mixer narrow-strips="yes" show-mixer="yes" maximised="no">
>     <geometry x-size="1753" y-size="765" x-pos="23" y-pos="179" x-off="0" y-off="0" mixer-rhs-pane1-pos="255" mixer-list-hpane-pos="75"/>

don3

2016-01-22 22:36

reporter   ~0017823

Last edited: 2016-01-22 22:37

Issue is still present on 4.6.96. The cause of the persistent failure seems to be this attribute of the Editor tag in instant.xml (see attached diff):

    zoom="2097152"

If I edit instant.xml and change just that number back to what it was in a working version (eg, 146919 in the attached example), I can open the session again without error.

As for how it gets set to the larger number, I still haven't isolated an exact trigger, but I'm able to reproduce it fairly well on an existing project simply by zooming (ctrl+scrollwheel) out quickly, to the scale of the session or beyond -- so it doesn't always need to involve horizontal scrolling. And my recent experiments have been in Grab mode, so it isn't unique to Draw mode.

Issue History

Date Modified Username Field Change
2015-12-16 01:34 don3 New Issue
2015-12-16 01:34 don3 File Added: instant.zombie-working.xml.diff
2016-01-22 22:36 don3 Note Added: 0017823
2016-01-22 22:37 don3 Note Edited: 0017823