[mythtv-users] backend 4x pvr250 MB advice

[Stephen Tait]

>
>
>Chris Kennedy (of ivtv hacking fame) has a box with 4 x 350s but with
>gigabit NFS and he noted on the ivtv list in the last 24 hours that
>using local disks might give problems (DMA). Not that it can't
>presumably be done with a powerful enough box.
>
>Sincerely,
>
>Adrian Phillips

Agreed. As the ivtv list states, the PVR cards are very heavy on IO and 
will thrash hard drives to within an inch of their lives. Get yourself some 
PCI IDE controllers and software RAID10 your drives, or (for preference) 
buy a 3ware, throw it into a PCI-X slot and do more RAID10.

Make sure your motherboard can handle all those IRQ's though. I picked up a 
Tyan S2466N-4M (aka Tiger MPX) quite cheaply which has 2 PCI-X 64/66 and 4 
PCI 32/33, which would seem up to the task, although I've never tried it 
with boatloads of cards, and the FAQ on the Tyan website reports it only 
has two discrete PCI buses. Personally though I'd spread the PVR-250's out 
amongst the frontends (and this would also give you flexbility in that 
you'd have the ability to swap one or two out for digital cards - I don't 
think Linux/Myth likes you mixing TV cards with DVB cards).