[mythtv-users] *Performance* of LiveTV auto recording?

[Steve Daniels]

> -----Original Message-----
> From: mythtv-users-bounces at mythtv.org [mailto:mythtv-users-
> bounces at mythtv.org] On Behalf Of Pekka Savola
> Sent: 18 April 2006 18:11
> To: mythtv-users at mythtv.org
> Subject: [mythtv-users] *Performance* of LiveTV auto recording?
> 
> Hi,
> 
> I want to be able to disable LiveTV's auto recording.  Well, I found this
> LOONG
> thread, but the only thing discussed was the problem with disk space
> required
> by LiveTV.

Yes, generally by people who didn't understand how the system works.

> 
> I don't care about disk space.  My reason is performance.  I don't have
> too
> fast a system (P3/800), and watching LiveTV already gulps about 180 MB of
> memory and about 30-50% of CPU.  I have done no measurements, but I
> suspect a
> non-trivial part of that is due to disk-I/O (yes, DMA is enabled).

A *doubt* that the high percentages come from writing and reading to and
from the disk respectively. Although you are using a lot of resources to
watch LiveTV, do you need these resources for anything else? What graphics
are you using? Try XVMC?

> 
> I'd argue the performance would be higher (significantly so?  I hope..) if
> you
> could just watch the DVB stream instead of unnecessarily "swapping" it to
> disk
> first.

Try using a program that allows you to watch the stream directly such as
mplayer, of kaffiene (spelling?) See what percentages you get.

> 
> Thoughts?
> 
> --
> Pekka Savola                 "You each name yourselves king, yet the
> Netcore Oy                    kingdom bleeds."
> Systems. Networks. Security. -- George R.R. Martin: A Clash of Kings

The thing about the way MythTV works, is there are A LOT of very good
reasons for it to work this way. For it NOT to write the stream to disk
first, which I believe it has done for quite a few versions, (it was called
a ring buffer in previous incarnations) would require extra coding, and you
would lose the PVR functions of Myth. So then people would ask why you are
using the MythTV PVR when you don't want to use the PVR functionality?

If you want to launch mplayer of kaffiene or tvtime or some other linux tv
program, look for the exectv function and build your own menu entry for it.
http://www.google.co.uk/search?hs=hUt&hl=en&safe=off&c2coff=1&client=firefox
-a&rls=org.mozilla%3Aen-US%3Aofficial&q=exectv+mythtv&btnG=Search&meta=

HTH

Steve Daniels