[mythtv-users] Recording storage suggestions

[Michael T. Dean]

On 05/23/2007 03:10 PM, Phill Wiggin wrote:
> I've been using Myth for a while now (since .14-.15ish) and have loved
> it.  However, I've had harddrives die, LVMs become unrecoverable, and
> run out of space more times than I care to count.
>   
...
> I was in a situation similar to yours, and I bought a new drive and
> upgraded to SVN.  My experience has been quite fruitful and I've had
> very few issues.
>
> I'd say your best bets would be:
>
>  - Stay with .20 and replace your current 160G w/ a 500G (or 750G).
>  - Upgrade to SVN and install your extra 160G for additional storage.
>   

I highly recommend against upgrading to SVN trunk just to get some new 
feature.  Using SVN trunk means that you're signing up to keep up with 
the development of MythTV--i.e. subscribe to and read /all/ the messages 
from the -dev and -commits lists and work your own way through most 
problems you encounter using the commit messages, source code, and the 
'net as your guide.

If you were to start using SVN trunk now, you'd actually have to read 
back through all the information that's come through -dev and -commits 
since the release of 0.20 (unless you're willing to leach information 
off people who have been following along).  It will be /much/ easier to 
upgrade when everyone else is doing so when 0.21 is released.  At that 
point, documentation--such as release notes and changelogs and tons of 
info on the wiki--will be available to "catch you up."  If you upgrade 
now, /you/ are responsible for doing all the research required to catch up.

If your plan is a "one-time-upgrade-to-SVN-trunk" just to get some 
features, leaching off others is not very considerate.  If, however, you 
do plan to keep up with Myth development from now on and to contribute 
code back into Myth, the leaching is more like "borrowing" (so make sure 
you pay it back :), but in truth, working through the code yourself is 
the best way to get the information/experience you need to start 
contributing to Myth development.

> I've convinced a few friends to use Myth (they now love it), and
> helped them decide on LVM.  Now that Storage Groups are available,  I
> can't recommend LVM for Myth.  I lost a nearly full ~1TB LVM set
> because one drive decided to give up the ghost.  My Myth recordings
> aren't anything 'high priority', but it's annoying to try to re-record
> everything. LVM adds points of failure to your whole recordings
> storage area; Storage Groups insulate you against that.
>   

I completely agree with everything you said in this paragraph except for 
the implication that you need to use either LVM /or/ Storage Groups.  I 
used an HDTV-only system with 5 HDD's spread out over 2 backends for 4 
months without LVM and without storage groups and never had any issues.  
The key is symlinks and something like myth_archive_job.pl (which can 
even be run automatically as a user job in Myth).

Basically, set up your system so that the recordings directory is your 
largest available partition (I like to use the largest hard drive I have 
available with a single partition).  When it fills up, use 
myth_archive_job.pl to move some recordings to other locations (on as 
many disks/filesystems as you like), thereby freeing up most/all of the 
space on the recordings directory.  Especially with SDTV, this is likely 
to mean you may have to organize your recordings once every 3 or 4 
months (depending, of course, on recording frequency and disk size) by 
finding a time when you won't be doing to much recording and typing 
"myth_archive_job.pl" into a terminal window (although you do need to do 
a one-time edit of the directory locations in the script for your system).

Mike