[mythtv-users] large mythtv deployment

[Josh White]

On Sat, Nov 15, 2008 at 4:32 PM, Josh White <jaw1959 at gmail.com> wrote:

>
>
> On Sat, Nov 15, 2008 at 2:38 PM, Michael T. Dean <mtdean at thirdcontact.com>wrote:
>
>> On 11/15/2008 02:05 PM, Michael Johnson wrote:
>> > On Sat, Nov 15, 2008 at 12:55 PM, Michael T. Dean wrote:
>> >
>> >> On 11/15/2008 11:40 AM, Michael Johnson wrote:
>> >>
>> >>>  On Sat, Nov 15, 2008 at 10:29 AM, Mike Perkins wrote:
>> >>>
>> >>>> Michael Johnson wrote:
>> >>>>
>> >>>>> I am doing a fairly large deployment of mythtv at work and I am
>> >>>>> looking for any pointers that may help us out. So far we have the
>> >>>>> following hardware for a mythtv cluster and we are now debating
>> >>>>> over the hd5500 or the WinTV-HD capture cards. We want 8x
>> >>>>> backends and 8x frontends.
>> >>>>>
>> >>>> Why on earth do you want to have eight backends? Are you setting
>> >>>> these up to be completely independant of each other? It's not
>> >>>> necessary, and you will be duplicating files and effort.
>> >>>>
>> >>>  We have 8 satellite feeds. So we don't necessarily want 8 backends,
>> >>>  however we want 8 capture cards hooked up (somehow) to the hardware
>> >>>  we have below.
>> >>>
>> >> Are you sure that will work?  Are you absolutely certain that you're
>> >> getting ATSC feeds from your satellite?  And, if so, are you absolutely
>> >> certain that these feeds are unencrypted?  If the answer to either
>> >> question is no, the HD-5500 (and likely--though I don't know the
>> >> hardware--the WinTV-HD) won't work at all.  Feel free to ignore me
>> since
>> >> it sounds like you have some special setup, so you probably know what
>> >> you're doing, but I just thought I would mention it just in case.
>> > when I say satellite feed I mean we have 8 satellite receivers in a
>> single
>> > room and we plan on controlling them with an ir blaster.
>>
>> Wouldn't that mean your only real option is the Hauppauge HD-PVR?  The
>> HD-5500 needs an unencrypted ATSC source (i.e. Over-The-Air broadcast
>> (8VSB modulation) or unencrypted cable (QAM modulation)).
>>
>> You cannot input Component/VGA/DVI/HDMI to an HD-5500.  TTBOMK, the only
>> thing you can use with Myth that takes an uncompressed HDTV signal (via
>> Component) is the HD-PVR.
>>
>> Still, though, the HD-PVR does all the compression for you, so the
>> backend would just be writing data to disk.  If you run commercial
>> flagging, the backend would also do that (though you can run
>> mythjobqueue on any machine--including a very powerful frontend--to run
>> commflagging jobs).  And, as Steve mentioned, transcoding is also
>> normally done by backends (but can be done by any mythjobqueue host, if
>> it has "local" access to the file--even using NFS or CIFS).
>>
>> Mike
>> _______________________________________________
>> mythtv-users mailing list
>> mythtv-users at mythtv.org
>> http://mythtv.org/cgi-bin/mailman/listinfo/mythtv-users
>>
>
> If you're going to have all your frontends and backends in the same room,
> why not use the dual/quad core machines you have as both frontends and
> backends?  From what I understand, the only reason to use a separate
> frontend and backend is due the load incurred by the tuner cards.  Most
> people don't want a loud, hot, large computer case in their livingroom, and
> therefore they build a backend to contain all the messy stuff, put it in a
> closet/garage/basement/etc. and put a more presentable machine near their
> display as a frontend.  If you're going to put all these machines in the
> same place anyway, then there's little reason I can see to not to use them
> as both frontend/backend machines (assuming I/O isn't a problem).  From the
> hardware you describe, you should have plenty of computer to do both with
> any of your machines.  If I were working on this, I would probably use the
> dual/quad core machines to handle it all, and then you should be able to
> reserve at least one cpu core per machine for commercial flagging, and at
> least one per machine for displaying the content.  Assuming your machines
> have at least 2 PCI slots/motherboard, that should allow you to use 8 single
> tuner cards, and each machine should have plenty of USB ports to handle the
> remote and ir blaster.  That way, instead of running 12 power supplies,
> you're only running 4 (though if you plan to heat the facility with the
> waste heat from the myth system, then maybe this isn't a benefit).  Perhaps
> using one or two of the P4's to house a raid array would make sense; if you
> were to have a large video collection in addition to the recordings you
> intend to create.
>
> That's my $.02, good luck; it sounds like you have an interesting project
> on your hands.
>
> -Josh
>
I guess I assumed the 3ghz single core machines were P4's...whatever.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://mythtv.org/pipermail/mythtv-users/attachments/20081115/8d51033d/attachment.htm