HDTV storage needs

[richb-RBmg6HWzfGThzJAekONQAQ at public.gmane.org (Rich Braun)]

Here's what my server says about the working volume:

Total Disk Space:
 350 GB total, 292 GB used, 58 GB (or 17%) free.
 7 hours left, using your average rate of 17203 Kb/sec
 6 hours left, using your maximum rate of 18270 Kb/sec

I've got a RAID1 set up for this working volume on the disk mirror shared with
the system volume.  RAID5 is set up for a collection of archive volumes:  if I
want to keep a program indefinitely, I'll move it into the archives and free
up the working volume.

A terabyte can hold 55 hours of raw video, more if you transcode it.  One
issue I have with MythTV's documentation is that it really doesn't explain
transcoding well enough, and the user interface doesn't help much there
either.  I've been too overwhelmed with other projects to figure out that part
of the system, and frankly I'm enough of a purist that I'd rather keep raw
footage and throw money at hard drives anyway.  They're insanely cheap now,
you could buy 5000 hours' worth of storage for the price some people pay for a
single wall-mount TV.

Use software RAID (at minimum) for your storage.  The drives and the software
are plenty fast enough.  I'm guessing that few people here are backing up
their video volumes--I'm not yet, despite all my past disasters--because of
the sheer size and difficulty of accomplishing it.  RAID won't protect you
against a burglary or a fire, or the more-likely fat-fingering of some command
that you regretted, but in the absence of backups it gives some peace of mind.
 Since drives are competitively priced on a per-gigabyte basis regardless of
drive capacity, divide your budget across 3 to 6 drives and plug them into a
motherboard that's got 6 SATA ports.  You can also save electricity by setting
the spindown timer on those drives which hold your archive recordings.

As for how much to spend on this--I dunno, my old Toshiba PVR held 40 hours'
worth which gave me a couple months' worth of TV programs before I typically
had to clean out and archive stuff, so that's why I set live-recording volume
to hold about 20 hours' worth.  Active TV watchers will want more than that: 
but Myth provides fairly convenient ways to move recordings into your
permanent archive.  Think about it that way; and think about how you'll make a
periodic backup copy of the archive so you don't lose those precious programs
that the family likes to come back to again and again.  The archive will grow
over the course of your lifetime--but it's permanent and storage will keep
getting cheaper so 20 years from now, who knows, it might all fit in your
shirt pocket.

-rich