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Full Version: Buffer underruns on SMB playback despite correct buffermode in Gotham
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I am testing the latest nightly on Windows and I get occasional buffer underruns streaming from SMB over WLAN despite having set buffermode=1 (and seeing the cache being filled to approx 25MB in normal use when hitting 'o' with readbufferfactor=3.0). Experimenting with readbufferfactor (1.0 to 4.0) did not seem to really do much beyond 2.0 (though I have to admit I do not really understand what that thing is supposed to do). What am I missing? Is there any way to force buffer to be 100MB+ (the machine has 4G RAM so even with triple buffering, I have ample resources left)?

FWIW, I also get occasional cache full errors (especially when starting playback).
What does your advancedsettings.xml file look like?
I'm having the same issue as nupi. What I've figured out is that while the file is not yet all in the buffer, if the net goes down, the video will soon pause, no matter how much content is buffered. I'm guessing that the smb file-checking hangs something up in the code causing it to stall playback even though there is plenty of video in the buffer.

My testing method: I have the network buffering set to 500 MB and keep an eye on it with the "o"-key display. While the cache value is going up, I can turn off the wireless radio and the video will stop within something like 3-5 seconds, even with 100 MB in the cache. If instead the cache has reached the end of the show (as seen by the cache value starting to go steadily down), I can turn off the wireless and it keeps on playing just fine.

FYI, here's the network part of my advancedsettings.xml file:
Code:
<network>
    <buffermode>1</buffermode>
    <cachemembuffersize>524288000</cachemembuffersize>
    <readbufferfactor>3.0</readbufferfactor>
</network>

..wayne..
(2014-03-30, 09:47)WayneD Wrote: [ -> ]I'm having the same issue as nupi. What I've figured out is that while the file is not yet all in the buffer, if the net goes down, the video will soon pause, no matter how much content is buffered. I'm guessing that the smb file-checking hangs something up in the code causing it to stall playback even though there is plenty of video in the buffer.

My testing method: I have the network buffering set to 500 MB and keep an eye on it with the "o"-key display. While the cache value is going up, I can turn off the wireless radio and the video will stop within something like 3-5 seconds, even with 100 MB in the cache. If instead the cache has reached the end of the show (as seen by the cache value starting to go steadily down), I can turn off the wireless and it keeps on playing just fine.

FYI, here's the network part of my advancedsettings.xml file:
Code:
<network>
    <buffermode>1</buffermode>
    <cachemembuffersize>524288000</cachemembuffersize>
    <readbufferfactor>3.0</readbufferfactor>
</network>

..wayne..
Ah, well spotted. This could be related to the issues I reported here:

http://forum.xbmc.org/showthread.php?tid=189561

Something definitely seems to be broken about the handling of buffering in Gotham, and if buffermode is set to 1 (as I use) the broken behaviour is extended to SMB filesystems as well...
I should mention that when I say "the video will soon pause" I don't mean pause in a normal, pause-screen or buffering manner, but it totally hangs up xbmc and makes it becomes non-responsive.

So, I'm assuming from my reading of the bug-reporting docs that there's no need to open up a trac bug report on an issue being discussed in the forums, right? I'd be glad to put some info in trac if that would be helpful...
If you have constructive examples, reproduction of issue and debug logs - these are always useful @ trac (added to the appropriate ticket) - otherwise valuable intel may not reach the devs handling the ticket. Can't really expect them to know the entire contents of the forum Wink