[Approved] Fix for stuttering/corrupted streaming of live tv

DJBlu

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August 14, 2007
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miroslav

This has improved zapping speeds on my network. By about 1second-2seconds on HD Channels. SD channels taking less than 2 seconds to change now.

Thanks.

edit:

Try unticking the "Don't drop discontinued packets in TSReader"

When there is a Continuity error the TVserver crashes without an error log.

With it enabled it doesn't happen.
 

miroslav22

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  • September 4, 2009
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    Great it's nice to hear it's improved people's setups, if anyone does notice any problems let me know.

    Since the patch seems to work nicely for people who have been testing it would be nice if:

    1) radio and video buffer size is changed to be detected on runtime
    2) someone can review the patch completely (the sooner the better :))
    3) MPFileWriter will be patched as well (and tested)
    I'll try and get this done tomorrow and post another patch. I determined 43 packets does seem to work the best. I did try 86 and 172 but both gave occasional continuity errors.


    Hi guys, sorry to interrupt, but does this patch also apply to single seat?
    Yes sorry I should have mentioned in the first post. If you are seeing stuttering/corruption on a single seat (and this is being caused by an overloaded disk rather than a signal/codec problem) then this *should* fix it (or at least improve it significantly)
     

    tourettes

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    Try unticking the "Don't drop discontinued packets in TSReader"

    When there is a Continuity error the TVserver crashes without an error log.

    With it enabled it doesn't happen.
    The setting has no effect on server side, only TsReader and the rest of the graph so it wont affect the server crashes at all (I would say it is placebo effect that it cured the server crashing).
     

    miroslav22

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    @Miroslav

    This has improved zapping speeds on my network. By about 1second-2seconds on HD Channels. SD channels taking less than 2 seconds to change now.

    Thanks.

    edit:

    Try unticking the "Don't drop discontinued packets in TSReader"

    When there is a Continuity error the TVserver crashes without an error log.

    With it enabled it doesn't happen.
    Yes I noticed zapping times seem to be better, little puzzled as to why this would improve it though :confused: Perhaps as there are less IOs queued a new buffer can be created more quickly.

    It's strange you saw a crash, was this whilst streaming? Were there any continuity errors in tswriter.log? There is seperate bug in tswriter that can crash tvservice when bad packets enter the filter. It's happened a few times for me when it's been raining heavily (bad signal).
     

    wouter1971

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    I see some stuttering on my prod xp system ocasionaly. On the HD channels only also curruption. If i jump back -15s it works again, and if it does it again i have to stop/start tv again to make it nice and clean again. This happens random. I installed the patch on my svn build test system and it improves channel switching. I have to go through other HD tests to see if the corruption is gone also. I have an SSD disk so speed should not be the issue. I'll continue testing. Thanks miroslav22
     

    miroslav22

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    hhmm maybe this is deeper than I thought if you're seeing this problem with an SSD disk. My theory was that the disk seeking times were the main cause of the issue, but as you say this would be negligible on an SSD disk.

    If you could let me know how you get on it would be much appreciated :)

    thanks
     

    disaster123

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    AW: Fix for stuttering/corrupted streaming of live tv

    miroslav22
    With your patch HD is now working without any problems on all of my clients the first time - channel changes are also faster. Sadly i have from time to time (1-3 times an hour) slow motion pictures... for about 5-20s then it is running fine again. But perhaps this get's fixed with fixing mpfilewriter. Thanks again for your patch it goes def. in the right direction.
     

    mm1352000

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  • September 1, 2008
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    Hi everyone

    Awesome work miroslav22! Thank you for your efforts :)

    I see some stuttering on my prod xp system ocasionaly. On the HD channels only also curruption. If i jump back -15s it works again, and if it does it again i have to stop/start tv again to make it nice and clean again. This happens random.
    I also experience this on occasions. When I get corruption, it often repeats periodically - maybe every 5 seconds - for 30 seconds or so, then it sometimes clears up. Other times it leads to major frame or frame-rate drops, probably because the codecs, renderers, or hardware acceleration are upset (???) - picture looks slow and jerky. Skipping back 15 seconds *always* solves it. Occasionally I get genuine signal problems which give similar symptoms. In that case skipping back won't solve the issue, but that is *very* rare...

    This is a frustrating problem to track down because I can't seem to find a consistent way to trigger it.
    I think it definitely doesn't help if you have slow HDDs.
    I don't think it matters whether the HDD slowness is due to having 5400rpm drives (not the case for me), or highly fragmented and full drives for timeshifting/recording (definitely true for me ;))
    The reason I mention HDDs is that for about a year I have been using a partition on a very full Samsung 750GB 753LJ 7200rpm drive as my timeshifting and recording drive. The drive possibly had 50 - 100GB of free space in total. It was *very* fragmented and one of the other partitions contained my OS. Far from ideal, but I had no other free space in the entire system and no free SATA ports. Too many MP recordings ;). The point is that I experienced the corruption issue quite frequently while I was in that situation, even when only watching MP in full screen mode. I usually only watch 720p or 1080i channels so I can't say whether the issue was HD only or both SD and HD, anyhow...

    Within the last 2 weeks I have bought two Samsung 2TB 5400rpm drives. I've freed up a lot of space and I'm now using a dedicated 7200rpm drive with lots of free space (500GB or so) for timeshifting and recording. I haven't noticed the issue at all since I got the new drives. Perhaps a coincidence, but I still think the high IOPS on a fragmented and full drive could have been the cause of my issues...
     

    DJBlu

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    August 14, 2007
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    @Miroslav

    This has improved zapping speeds on my network. By about 1second-2seconds on HD Channels. SD channels taking less than 2 seconds to change now.

    Thanks.

    edit:

    Try unticking the "Don't drop discontinued packets in TSReader"

    When there is a Continuity error the TVserver crashes without an error log.

    With it enabled it doesn't happen.
    Yes I noticed zapping times seem to be better, little puzzled as to why this would improve it though :confused: Perhaps as there are less IOs queued a new buffer can be created more quickly.

    It's strange you saw a crash, was this whilst streaming? Were there any continuity errors in tswriter.log? There is seperate bug in tswriter that can crash tvservice when bad packets enter the filter. It's happened a few times for me when it's been raining heavily (bad signal).
    Yer m8,

    Everytime on continuity errors, It was when I was changing channels too.
     
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