[mythtv] [mythtv-commits] Ticket #2708: patch: Allow remote FE/BE to prefer to use the myth protocol

[Yeechang Lee]

Mark Buechler <mark.buechler at gmail.com> says:
> I tried switching to samba for my frontend recordings mount and that helps a
> great deal.

This is consistent with my experience on a 3.0GHz Pentium 4 dedicated
frontend/backend box with a NAS for recording; see
<URL:http://www.gossamer-threads.com/lists/mythtv/users/169825#169825>.

> I don't get get high IO wait times anymore but HD playback still
> isn't perfect. If anything on the frontend or backend takes extra
> CPU, like EIT on the backend or mysql, I get stuttering.

In my case, HD playbacks are fine with no recording going on and with
a mythtranscode job. Once one or more of my three HD recording sources
(two FireWire and one HD-5000) starts up, I get the dreaded NVP:
waiting for prebuffer messages in one half- to two-second spurts. The
odd thing is that they are seemingly random; playback can be perfect
for a minute or two at a time, then the prebuffer messages come up for
a second or two, then might recur two seconds later, 20 seconds later,
or 90 seconds later.

As I noted elsewhere in the thread, using a combined frontend/backend
makes it problematic for me to try the Myth streaming protocol instead
of CIFS (or NFS). I'm sure I could do something with mount permissions
to force mythfrontend to resort to streaming but had never bothered as
I'd never considered that doing so might (emphasis on "might") deliver
better performance; however, had this been available as a configurable
option I'd surely have tried it by now, so a patch to add such an
option would certainly be welcome. I think I'm going to also try
fiddling with REQUEST_BLOCK's size in the source code, and would again
love to see this as a configurable option.

-- 
Yeechang Lee <ylee at pobox.com> | +1 650 776 7763 | San Francisco CA US