[mythtv-users] Frontend for HD Content question.

[Jim Carter]

On Wed, 10 Dec 2008, Fred Squires wrote:

> On Wed, Dec 10, 2008 at 10:29 AM, Nick Ellson <grimm at nickellson.com> wrote:
> > When I use the MythTV Tuner to select my HDHomeRun Tuners, I see the HD
> > content on my HDMI output, but it has a noticable jerkiness to it. 
==snip==
> > And, would I be correct in my assumption that to watch HDTV live, my
> > Mythbackend is streaming the content from my HDHomeRun to hard disk, and
> > then re-streaming that file to my FrontEnd for playback?

Yes, exactly right, although if you navigated backwards (rewind) you can be 
watching anywhere in the recorded file, not necessarily in strict real 
time.  Even for live TV the backend records the content, to enable such 
navigation.

==back to Fred Squires==

> I had a similar issue with my HDHomeRun, it turned out I was having
> network issues on my 10/100 network. 
==snip==
> What I did to solve this was I added a second network adapter to my
> backend...

I haven't gotten enough experience to make actual measurements, but I doubt 
that 2 HD subchannels would saturate a 100MHz network.  But if one of the 
network cards (most likely on the backend) were mismatched with the network 
switch, that would really mess up throughput.  Can you try to transfer a 
big file between the frontend and backend, and see how long it takes?  
"scp" will calculate the data rate for you.  12.5 Mbyte/sec is the 
theoretical maximum for 100baseT wired Ethernet, and my machines do 9 to 10 
Mbyte/sec in practice, in a test like this.

James F. Carter          Voice 310 825 2897    FAX 310 206 6673
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