[mythtv-users] Both In progress HD recordings and Live Tv dropping frames on frontend.

[John]

On 12/05/14 12:31, Angela wrote:
>> When I watch in-progress recordings or LiveTV on the frontend ( Atom), It
>> stutters, and looking at the logs for mythfrontend -v playback I can see
> it is
>> dropping Video frames. The extent of drops varies. As soon as the
> recording
>> stops, the same file continues to play smoothly without drops.
> Stuttering issue is described in https://code.mythtv.org/trac/ticket/12016
> Possible problems are:
> - MySQL on ext4, barriers problem
>         either move your DB to a ext3 filesystem, or add "barrier=0" in your
> mount command (/etc/fstab, eg. /dev/sda5    /    ext4    noatime,barrier=0
> 0    1).
> - Some of your MySQL tables use the InnoDB engine, check your backup sql
> files for "ENGINE=InnoDB"
>         backup your DB, with a normal editor change "ENGINE=InnoDB" with
> "ENGINE=MyISAM" and restore
> http://www.mythtv.org/wiki/Database_Backup_and_Restore.
>
> Hope this helps,
> Angela
>
>

Angela



Thank you for your reply. Your ticket reads exactly like my problem, and 
I have tried some of the solutions ( without patching the code)

I have already mounted without barriers:

/dev/sdf1 on / type ext4 (rw,noatime,barrier=0,errors=remount-ro)


The only tables using

"ENGINE=InnoDB"

are mythweather related table, which I assume are irrelevant ?.

I still see this problem. The dropped frames are not at exactly 10 sec 
intervals, but as soon as the recording stops, the dropped frames stop. 
I assume there is something similar to the problem you have fixed by 
increasing dbase query speeds, and either the similar changes haven't 
increased the speed, or there are other drags on the system.

I am intrigued by what the difference is between the frontend being in the

kState_WatchingRecording rather than kState_WatchingPreRecorded, as I assume it is the dBase activity of being in the former state that causes the issue. As the backend shouldnt care if a frontend is watching somthing its recording, nulling out that activity seems to make sense.


thanks again, John