[gst-devel] playback hangs with wallclock change

[Wim Taymans]

On Fri, 2010-03-26 at 09:41 -0300, Babineau, Denis wrote:
> Hi,
> 
>  
> 
> I’m thinking this might be a bug report but I thought I’d run it by
> the mailing list first. I’m having an issue where video
> stutters/freezes completely when the system clock is changed. I can
> cause this to happen by simply playing  a video with playbin (in this
> case a theora stream) and moving the clock ahead and back. For
> example, if I move back the clock 1 minute, the video will hang for 1
> minute. I have a callstack that looks something like so:
> 

What version of GStreamer is this? The clock has been using the
MONOTONIC clock by default since version 0.10.24 (and performance
counters on Windows since 0.10.25).

Wim

>  
> 
> #0  0xffffe410 in __kernel_vsyscall ()
> 
> #1  0xb794ce50 in ppoll () from /lib/libc.so.6
> 
> #2  0xb7b50db3 in gst_poll_wait (set=0x8468af0, timeout=63569646) at
> gstpoll.c:1131
> 
> #3  0xb7b5e509 in gst_system_clock_id_wait_jitter_unlocked
> (clock=0x8647848, entry=0x863cbb8, jitter=0xb1fa2be0, restart=1)
> 
>     at gstsystemclock.c:569
> 
> #4  0xb7b5ec73 in gst_system_clock_id_wait_jitter (clock=0x8647848,
> entry=0x863cbb8, jitter=0xb1fa2be0) at gstsystemclock.c:658
> 
> #5  0xb7b231ea in gst_clock_id_wait (id=0x863cbb8, jitter=0xb1fa2be0)
> at gstclock.c:381
> 
> #6  0xb612806f in gst_base_sink_wait_clock (sink=0x813a020,
> time=4733333333, jitter=0xb1fa2be0) at gstbasesink.c:1689
> 
> #7  0xb612ab07 in gst_base_sink_render_object (basesink=0x813a020,
> pad=0x8138850, obj=0x85abc10) at gstbasesink.c:1978
> 
> #8  0xb612c6b5 in gst_base_sink_queue_object_unlocked
> (basesink=0x813a020, pad=0x8138850, obj=0x85abc10, prerollable=1)
> 
>     at gstbasesink.c:2558
> 
> #9  0xb61314dd in gst_base_sink_chain_unlocked (basesink=0x813a020,
> pad=0x8138850, buf=0x85abc10) at gstbasesink.c:2916
> 
> …
> 
>  
> 
> The timeout (nanoseconds) in frame 2 appears to be reasonable given
> the framerate, however it seems to be looping somewhere on those
> calls. I have yet to delve deep enough into the code to completely
> understand the clock synchronization but is there something that would
> easily allow me to change the clock to perhaps rely on the
> CLOCK_MONOTONIC time instead of CLOCK_REALTIME? (which appears to be
> the case)
> 
>  
> 
> Thanks
> 
> Denis
> 
> 
> CONFIDENTIALITY NOTICE: The contents of this email are confidential
> and for the exclusive use of the intended recipient. If you receive this
> email in error, please delete it from your system immediately and 
> notify us either by email, telephone or fax. You should not copy,
> forward, or otherwise disclose the content of the email.
> ------------------------------------------------------------------------------
> Download Intel® Parallel Studio Eval
> Try the new software tools for yourself. Speed compiling, find bugs
> proactively, and fine-tune applications for parallel performance.
> See why Intel Parallel Studio got high marks during beta.
> http://p.sf.net/sfu/intel-sw-dev
> _______________________________________________ gstreamer-devel mailing list gstreamer-devel at lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/gstreamer-devel