[mythtv-users] Tuning a mythtv box to stop jittering...

[stuart]

Hi...

I'm having a difficult time w/a single core MBE mythtv box.  It jitters 
when playing 1080i live and recorded programming.  It can almost handle 
720p live and recorded programming.  It can usually handle OTA SD ATSC 
and NTSC recordings.

(
Important stuff:
model name      : Intel(R) Celeron(R) CPU 3.06GHz
cpu MHz         : 3073.674
cache size      : 256 KB
MemTotal:       906292 kB
Model:           GeForce 6200
Card Type:       AGP
This box is using 1 Logical Volume made up of 6 partitions on 3 Hard 
Drives (2 IDE and 1 SATA).
)

Also of note, a duel core SBE which plays it's own HD programming w/o 
problems usually jitters when pulling a program from the above MBE box. 
  And, depending if the MBE box is commercial flagging, will even have 
problems pulling SD programming.

I have improved (not fixed!) the ability of the MBE to play back 1080i 
and 720p programming by changing the HDD latency.  However, these 
changes appear to not help at all if the MBE is doing any commercial 
flagging.  Also, I'm not sure why this box had not only an IDE latency 
setting but also a RAID latency setting.  Perhaps that is a consequence 
of the way the mother board is built.  I changed both just to make sure.

I don't believe I am using hardware based de-compression.  That makes it 
difficult to edit videos.  Plus, I was under the impression that a 3GHz 
processor would be able to handle HD programming.

I do have the mysql data base rolled into the same Logical Volume as the 
  recorded programs.  I've seen suggestions to put the data base on it's 
own HDD, but I'm not sure how important this is.

Also, I've noticed that I had divided my STAT HDD into 4 partitions 
before recombining them into the 1 Logical Volume used for everything on 
this box.  Could that compromise the performance the the HDDs?

...thanks for any help.