[mythtv-users] RAID using two drives per PATA channel ?

[Brad Templeton]

On Mon, Jul 31, 2006 at 04:22:03PM -0400, Steven Adeff wrote:
> right, I'm just wondering if doing so along with adding two more
> drives to the controller for the RAID10 will have an overall speed
> increase or not. the other option is to get a 4-port SATA controller
> and buy 4x300GB drives (and do what with my current 300GB PATA drives
> I ask myself...)
> 
> My case can only handle 6 harddrives, so my recordings drive will only
> ever be 6 drives total, so these are pretty much my only two options
> without buying a new motherboard. (unless anyone knows of a socket 939
> nforce based mobo with 5xPCI slots with 6SATA ports that works well in
> linux?)

Since you are asking this on a myth group, it is worth noting that
hard disk read/write performance is only of marginal importance on
the myth video recordings partition.   No function there that I
know of is even remotely I/O bound -- not recording, not playback,
not transcode nor commercial scan.    Only direct copying of large
files (which I see little reason to do) would be I/O bound.

So this suggests it's perfectly fine to do a myth raid group with
master/slave.

On the other hand, high performance is desired for your regular linux
partitions.   They are of course much smaller.  You might consider
raid 1+0 on 4 drives for them, and raid-5 on 4 drives for the video
files.   (Software raid, typically for this ability.)