[mythtv-users] Lengthy delay watching recordings

[Michael T. Dean]

On 05/22/2012 02:19 PM, Rich West wrote:
> I noticed that going to 0.25 about a month back that the delay to start
> playing an HD video had increased substantially and was curious as to
> what might be the cause.
>
> As I looked further, I realized that it is with all video, but HD
> content appears to be the most obvious offender.  It can take up to 31
> seconds from the moment the user selects the video to play before it
> actually starts playing.
>
> My backend system is well used, but from the graphs I have, it's not
> hurting with CPU or memory.  Network to the frontends are all hardwired
> (backend is gig, frontends are 100 meg).  From a utilization
> perspective, the drives on the backend server are always hovering at
> around 85% utilization, which is good, and the general I/O on the drives
> is not such that it would cause a negative impact.
>
> I am using commercial detection, so I do suspect that there is some form
> of buffering going on, but for 31 seconds?  No network errors on the
> switch or the interface for the frontend or the backend.    CPU
> utilization on the frontend is low.. basically idle.
>
> I'm just wondering if there is a particular place within MythTV to look
> (for example, I recently found that it was recommended that "quick
> tuning" should be enabled for the hdhomerun)..
>

/me guesses you have MySQL data on a file system with barriers enabled.

Mike